This discussion has bee very helpful as I have the same problem. I bought a new 2022 Apple TV 4K in early December. It worked fine for a couple of weeks, then two times the remote failed to turn on the Sony TV and Apple TV. I unplugged the HDMI cable and power cord to the Apple TV to get them working. After the second failure, I bought a replacement HDMI cable thinking CEC might have a problem with the old cable. Same problem.
After I got it working after the second failure, it worked fine for a few days, then I got the "Remote disconnected." I charged the remote and followed the re-pair instructions. It worked fine for 10 seconds and then "Remote disconnected." I re-paired it a second time and it worked fine for another 10 seconds and disconnected.
My old Roku Ultra worked fine nonstop for five years. I just wanted to upgrade to 4K. My previous Apple TV worked fine for about 10 years. My wife's Sharp Roku TV (built-in Roku) works fine.
What a piece of junk this 2022 Apple TV 4K is! Come on, Apple. What has happened to your legendary quality!?
To make it worse, all of these fixes are a HUGE pain in the neck because I have the Apple TV attached to the back of the 65" TV on the wall with Velcro. Every time it fails, I have to get out my step ladder to access the unit and wires behind the TV.