You are probably right for something like a Pihole, which can easily run on a RPi 3 as well (I think I’m running it on a 3… maybe even a 2.) My fear is something like Jellyfin (which it is not suited for anyway, I know), combined with the fact that my stack of Pis is in my meter cabinet, so a fairly confined space with very little air movement, also passive. Running Jellyfin without transcoding has my Pi 5 running at just under 50 °C.

damn you all, now I impulse bought an old thin client for 30EUR :-) but, fwiw: I mostly use RPi for my purposes, up to RPi4; RPi 5 I think missed the mark, with its active cooling requirement and power use. (and price…) the only use case where an i86 alternative is justified is my jellyfin setup (where realtime transcoding is needed).