“Oh god, they will immediately be able to tell I am a fraud who has no idea what he’s doing when I tell them I use Ubuntu”

Ubuntu is fine and I actually am on Ubuntu after using Arch for many years

Isn’t Arch a lot of manual compilation? Like I do that shit for work, I don’t want to do it in my free-time too.

No, Arch has recompiled packages. Maybe you think of Gentoo?