Discord would be the obvious answer, but I understand why you might want to use it, my recommendation is using a client that disables some of the tracking like Vesktop. Spotify is also a major privacy concern, it can be replaced by Spotube (and to a lesser degree by Audiotube) which removes most tracking and is three and convenient. Also I’m not sure if I would keep using chromium, especially with manifest V3

FediDB

They will find you were ever you are

I think the main reason is that most people who use Linux installed it on their own and at that point no parental control is stopping you.

What about Epiphany/Falcon? They are AFAIK built from scratch, apart from the engine. Would you still consider them clones?

Nobara doesn’t use Firefox from fedoras repos, that’s why it is outdated. The Firefox flatpak is officially from Mozilla, or you can download the latest .tar.gz from their website, but then you won’t have the regular update system.

Parental controls are one of the under developed parts of Linux, the only major one I know of is timekpr

My recommendation would be setting up Nobara with a separate home partition so you can easily switch if it stops being supported, although there are no sign of this yet. My second recommendation would be Opensuse Leap, it is more stable and well established but less optimized for gaming. Maybe take another look at Pop OS! when they release their independent new desktop. If you go with base Fedora be aware setting up codecs can be annoying. Avoid Manjaro, the distro breaks a lot due to dependency conflicts. Also I think you mean GNOME 40, GNOME 3 is the old design.

Not sure, but maybe this is a pipewire vs pulseaudio thing. Enable pipewire on Debian

Probably still working on the deep fake

Peertube/Odysee exist, even if they are relatively niche.