well, I've had a few frustrations with hdmi-cec. both the series x and the ps5 seem to have limited options, which don't work too well with my tv. I got my tv back in February, so I'm just starting to learn about hdmi-cec and smart tvs (never owned one), but my ps5 would turn on whenever I turned on the tv, when I pretty much wanted the reverse, tv turning on when I press the playstation button on the ps5 controller. that's why I turned off the option. I can't recall why I turned off the option on the series x, but probably similar frustrations with the options provided.
I don't know which leak you're referring to, but I use that thread to get up-to-date news about the ps5 and then his other thread about the ps4 for the same reason. I try to compile everything that's mentioned, since a lot of things for the ps4 and 5 you're left to compile on your own. I'm a part of three discord servers, but I really only post in one of them (mostly about compiling). there are a lot of people who struggle with it, so I thought I'd share my knowledge on there and here, since I've gotten halfway decent at it. I've gained a lot of knowledge about both systems that way despite not owning a ps4 nor a hackable ps5.