This was just posted on the Windows newsgroups, but it applies equally to
those on these specialty newsgroups who search before they ask questions.
*Web-searchable (read only) Google Groups Archives for this newsgroup*

NOTE: These are deprecated special-purpose "newsgroups" for Mozilla servers
<https://groups.google.com/forum/#!forum/mozilla.general>
<https://groups.google.com/forum/#!forum/mozilla.support.firefox>
<https://groups.google.com/forum/#!forum/mozilla.support.thunderbird>
etc.

Which were copied to the following simpler URLs in the great reshuffle:
<https://groups.google.com/g/mozilla.general>
<https://groups.google.com/g/mozilla.support.firefox>
<https://groups.google.com/g/mozilla.support.thunderbird>
etc.

Paul wrote:

> Google Groups stopped adding groups, some time ago.
>
> It has added a ton of its own private groups.
> Which nobody cares about.

Hi Paul,

I often run a search before asking questions, and when researching
issues to help answer others, so I've been involved in this for years.

I think your assumption is not quite accurate, as I have been using Google
Groups archival links for many years, but I didn't do any explicit research
so it's just my "experienced assumption" that Google _does_ add groups.

They're just extremely selective about which groups they bother to add. :)
<alt.usage.english>
<news.software.readers>
<alt.free.newsservers>
<comp.text.pdf>
<alt.comp.software.thunderbird>
<alt.comp.software.firefox>
<rec.photo.digital>
<rec.autos.tech>
<alt.home.repair>
<alt.comp.microsoft.windows>
<microsoft.public.windowsxp.general>
<alt.comp.os.windows-11>
<alt.comp.os.windows-10>
<alt.comp.os.windows-8>
<alt.windows7.general>
<alt.msdos.batch>
<alt.os.linux>
<comp.mobile.android>
<comp.mobile.ipad>
<misc.phone.mobile.iphone>
<alt.comp.freeware>
<comp.sys.mac.apps>
<comp.sys.mac.system>
<comp.sys.mac.advocacy>
<alt.internet.wireless>
<sci.electronics.repair>
<sci.geo.satellite-nav>
etc.

It was well before Google changed their archival links to something easy
to remember when the "N" archives used exactly those monikers, namely:
<https://alt.usage.english.narkive.com>
<https://alt.free.newsservers.narkive.com>
<https://news.software.readers.narkive.com>
<https://comp.text.pdf.narkive.com>
<https://alt.comp.software.thunderbird.narkive.com>
<https://alt.comp.software.firefox.narkive.com>
<https://rec.photo.digital.narkive.com>
<https://rec.autos.tech.narkive.com>
<https://alt.home.repair.narkive.com>
<https://alt.comp.microsoft.windows.narkive.com>
<https://microsoft.public.windowsxp.general.narkive.com>
<https://alt.comp.os.windows-11.narkive.com>
<https://alt.comp.os.windows-10.narkive.com>
<https://alt.comp.os.windows-8.narkive.com>
<https://alt.windows7.general.narkive.com>
<https://alt.msdos.batch.narkive.com>
<https://alt.os.linux.narkive.com>
<https://comp.mobile.android.narkive.com>
<https://comp.mobile.ipad.narkive.com>
<https://misc.phone.mobile.iphone.narkive.com>
<https://alt.comp.freeware.narkive.com>
<https://comp.sys.mac.apps.narkive.com>
<https://comp.sys.mac.system.narkive.com>
<https://comp.sys.mac.advocacy.narkive.com>
<https://alt.internet.wireless.narkive.com>
<https://sci.electronics.repair.narkive.com>
<https://sci.geo.satellite-nav.narkive.com>
etc.

At the time I had used a combination of N archives & google groups links
which were the best I could do then to publish web-searchable archives:
<https://tinyurl.com/alt-usage-english>
<https://tinyurl.com/news-software-readers>
<https://tinyurl.com/alt-free-newsservers>
<https://tinyurl.com/comp-text-pdf>
<https://tinyurl.com/alt-comp-software-thunderbird>
<https://tinyurl.com/alt-comp-software-firefox>
<https://tinyurl.com/rec-photo-digital>
<https://tinyurl.com/rec-autos-tech>
<https://tinyurl.com/alt-home-repair>
<https://tinyurl.com/alt-comp-microsoft-windows>
<https://tinyurl.com/microsoft-public-windowsxp-gen> (30-character limit)
I also had created an easier URL:<https://tinyurl.com/windowsxp-general>
<alt.comp.os.windows-11> At the time this didn't exist for me to set up
<https://tinyurl.com/alt-comp-os-windows-10>
<https://tinyurl.com/alt-comp-os-windows-8>
<https://tinyurl.com/alt-comp-os-windows-7>
<https://tinyurl.com/alt-windows7-general>
<https://tinyurl.com/alt-msdos-batch>
<https://tinyurl.com/alt-os-linux>
<https://tinyurl.com/comp-mobile-android>
<https://tinyurl.com/comp-mobile-ipad>
<https://tinyurl.com/misc-phone-mobile-iphone>
<https://tinyurl.com/alt-comp-freeware>
<https://tinyurl.com/comp-sys-mac-apps>
<https://tinyurl.com/comp-sys-mac-system>
<https://tinyurl.com/comp-sys-mac-advocacy>
<https://tinyurl.com/alt-internet-wireless>
<https://tinyurl.com/sci-electronics-repair>
<https://tinyurl.com/sci-geo-satellite-nav>
etc.

Note these are all so old they link to the now-deprecated Google Groups
which had recently been DejaNews archived at that time of formation:
<https://groups.google.com/forum/#!forum/alt.usage.english>
<https://groups.google.com/forum/#!forum/news.software.readers>
<https://groups.google.com/forum/#!forum/alt.free.newsservers>
<https://groups.google.com/forum/#!forum/comp.text.pdf>
<https://groups.google.com/forum/#!forum/alt.comp.software.thunderbird>
<https://groups.google.com/forum/#!forum/alt.comp.software.firefox>
<https://groups.google.com/forum/#!forum/rec.photo.digital>
<https://groups.google.com/forum/#!forum/rec.autos.tech>
<https://groups.google.com/forum/#!forum/alt.home.repair>
<https://groups.google.com/forum/#!forum/alt.comp.microsoft.windows>

<https://groups.google.com/forum/#!forum/microsoft.public.windowsxp.general>
<alt.comp.os.windows-11> At the time this didn't exist for me to set up
<http://www.pcbanter.net/forumdisplay.php?f=52> for Windows 10
<http://www.pcbanter.net/forumdisplay.php?f=50> for Windows-8
<http://www.pcbanter.net/forumdisplay.php?f=48> for Windows-7
<https://groups.google.com/forum/#!forum/alt.msdos.batch>
<https://groups.google.com/forum/#!forum/alt.os.linux>
<https://groups.google.com/forum/#!forum/comp.mobile.android>
<https://groups.google.com/forum/#!forum/comp.mobile.ipad>
<https://groups.google.com/forum/#!forum/misc.phone.mobile.iphone>
<https://groups.google.com/forum/#!forum/alt.comp.freeware>
<https://groups.google.com/forum/#!forum/comp.sys.mac.apps>
<https://groups.google.com/forum/#!forum/comp.sys.mac.system>
<https://groups.google.com/forum/#!forum/comp.sys.mac.advocacy>
<https://groups.google.com/forum/#!forum/alt.internet.wireless>
<https://groups.google.com/forum/#!forum/sci.electronics.repair>
<https://groups.google.com/forum/#!forum/sci.geo.satellite-nav>
etc.

Which, after the great reshuffling, currently boil down to the following
much easier to remember and logically derived Google Groups search links:
<https://groups.google.com/g/alt.usage.english>
<https://groups.google.com/g/news.software.readers>
<https://groups.google.com/g/alt.free.newsservers>
<https://groups.google.com/g/comp.text.pdf>
<https://groups.google.com/g/alt.comp.software.thunderbird>
<https://groups.google.com/g/alt.comp.software.firefox>
<https://groups.google.com/g/rec.photo.digital>
<https://groups.google.com/g/rec.autos.tech>
<https://groups.google.com/g/alt.home.repair>
<https://groups.google.com/g/alt.comp.microsoft.windows>
<https://groups.google.com/g/microsoft.public.windowsxp.general>
<alt.comp.os.windows-11>
<alt.comp.os.windows-10>
<alt.comp.os.windows-8>
<alt.windows7.general>
<https://groups.google.com/g/alt.msdos.batch>
<https://groups.google.com/g/alt.os.linux>
<https://groups.google.com/g/comp.mobile.android>
<https://groups.google.com/g/comp.mobile.ipad>
<https://groups.google.com/g/misc.phone.mobile.iphone>
<https://groups.google.com/g/alt.comp.freeware>
<https://groups.google.com/g/comp.sys.mac.apps>
<https://groups.google.com/g/comp.sys.mac.system>
<https://groups.google.com/g/comp.sys.mac.advocacy>
<https://groups.google.com/g/alt.internet.wireless>
<https://groups.google.com/g/sci.electronics.repair>
<https://groups.google.com/g/sci.geo.satellite-nav>
etc.

In summary, I "think" Google _does_ add groups when _they_ see fit.
They just do NOT see fit to add Windows variants as archived groups.
--
Posted out of the goodness of my heart to disseminate useful information
which, in this case, is to faithfully elucidate group search archival URLs.