For years, if I allow the Win10 desktop to sleep, it never wakes up.

I don't know how to read the sleep study report (do you)?
C:\Windows\system32> powercfg /sleepstudy
Sleep Study report saved to file path
C:\Windows\system32\sleepstudy-report.html.

firefox file:///C:/Windows/System32/sleepstudy-report.html
https://www.imagevenue.com/ME13Y85T (this is a jpg of the sleep study)

C:\Windows\system32> powercfg /lastwake
Wake History Count - 0
C:\Windows\system32> powercfg /waketimers
There are no active wake timers in the system.

C:\Windows\system32> powercfg /requests
DISPLAY: None.
SYSTEM: None.
AWAYMODE: None.
EXECUTION: None.
PERFBOOST: None.
ACTIVELOCKSCREEN: None.

Keyboard is allowed to wake the computer but there is no power to the
keyboard as evidenced by the key lights not being turned on when sleeping.
Device Manager > Keyboard > Power Management
Allow this device to wake the computer = checked
I can press the (dead) keyboard all I want but it won't even light up.

Same with the mouse.
Device Manager > HID-compliant mouse Properties > Power Management
Allow this device to wake the computer = checked
I can wiggle the (dead) mouse all I want but the red LED won't light up.

Monitors have power. Just no signal from the Win10 desktop.

I don't know where to look to see if the BIOS can power the bottom two USB
slots in the back of the desktop (which are the ones for keyboard & mouse).

The power button is lit on the desktop but it does nothing when I long press
(or any kind of press). Same with wiggling the mouse (which will wake the
screen if it's just the screen that went to sleep).

Is there a way to log what happens moments before Win10 goes to sleep?

All the drivers have been updated many times over the years.
The monitors, mouse, and keyboards have been changed over the years.

These settings never wake up (Win+X > Power Options)
Windows Settings > System > Power & sleep
Screen > 10 minutes
Sleep = 30 minutes
Performance and Energy = Best performance

powercfg.cpl
Control Panel\Hardware and Sound\Power Options\Edit Plan Settings
Additional power settings
Preferred plans = Balanced (recommended)
Turn off the display = 10 minutes
Put the computer to sleep = 30 minutes
(there is no option to "turn on/off fast startup")

An administrator command window shows hibernation & fast startup off.
powercfg.exe /hibernate off

PCI Express Link State
control.exe powercfg.cpl,,3
PCI Express > Link State Power Management > Setting = Off
Sleep > Allow wake timers > Enable
USB Settings > USB selective suspend settings > Enable

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power
There is no "CsEnabled" value when the "Power" key is selected.

Other than shutting down manually and turning off the power manually,
do you have suggestions for how you were able to get out of sleep?