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I think there is a lot of "old web" still around but it depends on your interests and also with search engine enshittification it is hard to discover. BBSes seem pretty popular again in certain circles too - classic computing being the main one I would say.
Frank Sträter

@hamishtpb At this point the "old web" is also those fora from 2000-2010. I noticed some resurgence of phpBB. Example: lunarpunk.town/

lunarpunk.townlunarpunk.town - Index page