https://elektronauts.com
cycling:
https://velocipedesalon.com
https://forums.thepaceline.net
simracing:
https://simracingonline.co.uk
https://www.lfs.net/forum
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.