I've never seen a device that supported CEC where use of it wasn't toggled inside a menu. Both sides of the wire need to accept it.

I've seen millions of comments on AV forums from Apple TV users having problems with CEC.

I don't have an Apple TV. Does it have a setting to disable CEC?

TVs usually have an option to disable (i.e. ignore) it though, at least every one I've owned/helped someone with has.

I can disable CEC on the TV, but of course I want the TV to turn on when I wake up a device. I just want to be able to turn off the TV and have it not turn off the receiver. Picky, I know, but I gathered that we’re deep in “first world problems” here.

Sounds like there is a market for a CEC firewall box. Something $1 ESP8266 based you could configure with a phone/laptop over the air in visual way (webpage) to pick an d choose what can pass in what direction, maybe even with ability to add simple scripts triggered by particular messages. ~$5 BOM ~$15 retail.

I'd buy one.