This, I don't really understand this "bring back" things, there are a handful of forums I am visiting almost daily. And they are probably my most visited websites alongside hackernews and a couple of others.
cycling:
https://forums.thepaceline.net
simracing:
https://www.overtake.gg/forums/
And a few others I visit less frequently but I won't mention because I have already leaked a lot of information :-)
I guess there are still a ton of forums that cover a wide variety of hobbies/interests.
Arch Linux forums, using FluxBB: https://bbs.archlinux.org/
Free Pascal forums, using Simple Machines Forum: https://forum.lazarus.freepascal.org/
Python forums, using Discourse: https://discuss.python.org/
Nim forums, using their own nimforum software written in Nim: https://forum.nim-lang.org/
There's also Hardforum for hardware related discussions, though I don't visit as often anymore.
Many others I used to visit are dead.
Also f1technical.net
There's a Spain equivalent forum also if you poke around