TLDR: Is your keyboard plugged into a hub or directly into a USB port?
I've had my vintage 2003 Apple keyboard plugged into my monitor's USB hub since High Sierra. All sleep, wake and power functions worked fine. I skipped Catalina and, after converting from Clover to Opencore and Big Sur, eventually found it took two keyboard hits to fully wake the system and monitor. This bothered me some, though not enough to look for a solution.
After doing a test install of Monterey on OC 7.4, the wake issues got much worse. The system would only wake from sleep by pressing the power button, but magic mouse scrolling and othere things were broken, as noted by OP and others in this thread. Using pkill bluethoothd fixed the mouse and BT, but wasn't a satisfactory solution for me.
I tried changing BIOS settings, a handful of different BT kexts and UDSBPorts mods, with no success. On the other hand, I discovered that wake from sleep worked fine with the keyboard plugged directly into the front USB panel (Designare Z390 HS05-06/SS05-06.)
Googling "mac wont wake usb hub", there were a number of references, even as far back as 2011, about Macs failing to wake properly when a keyboard was attached to a hub, leading me to think this wasn't just a Hack issue. The general conclusion seemed to be that some hubs just don't wake from sleep well on Macs, so main input devices should be connected directly to a USB port on the machine.
In Big Sur (11.6.1, OC 7.5) I tried plugging the USB cable supplying the monitor hub into different system USB ports. After moving the cable from the Designare HS10 port (USB2 only) to one of the HS07/SS07 (internal) hub ports, a single keyboard entry worked to completely wake from sleep - even though the keyboard was still attached to the monitor hub.
Back in Monterey, the change made no difference. Only bypassing the monitor hub all together and plugging the keyboard directly into an HS07/SS07 port fixed the problem. A single keyboard hit completely wakes the system, with no mouse scrolling or other issues, as far as I can tell.
As usual, YMMV? Big Sur will probably remain my OS of choice until after the 12.1 update, so I won't be testing this much further for now. But maybe this will provide some clues to others users the developers as to what is going on....