I switched away from Gentoo a few years back because I don't feel I have the CPU time to compile all the packages on my laptop. Now I run Gentoo on my Steam Deck because I need to customise the thing so badly.
CPU time has never been an issue for me, really. I am intrigued by Gentoo on a SteamDeck - how well does that work? I imagine a very tight thermal headroom gets in a way every now and then.
Gentoo on Steam Deck works great. The kernel must have all the drivers now. For audio it must use Pulseaudio/Pipewire for the speakers to work. Compiling Firefox just takes about two hours? I didn't time it. If it's not compiling then it has no noticeable heat pumping out.