I kind of dislike Discourse. They hijack the ctrl+F search, they lean too heavily on "infinite load", it's just too ajaxy. I used to use old.reddit.com, so that's what I enjoy. Just load the markup and get out of the way.
I never understood the appeal of Discourse. It feels heavy with an overutilization of negative space. The D programming language forum is a good example of a well-designed forum in my opinion.
If you want to use something lighter, Flarum exists, modern but lightweight built using PHP.
The grapheneOS forum uses, but I like discord because its more advanced with many features and integrations.
Discourse*
I don't like their infinite scrolling instead of normal pagination.