> discuss things with people in private, invitation only forums
One of the great things about not having ads on rangerovers.pub is that Google is just not interested in indexing it, because it doesn't make them any money. It shows up here and there in search results, sporadically, especially if you know a username or phrase specific to the site, but other than that if you want to know about it you need to be told about it.
I was never a fan of web forums but they are a nice compromise between really oldschool mailing lists and FAANG content-to-eyeball transformers.
I have seen a bit of a resurgence in your classic 2005-era type interface php bulletin board in a browser, as people relegate their facebook/instagram/whatever accounts to only keeping up with family stuff posted by boomers who won't use anything else, or things like niche neighborhood based buy & sell groups (or community notice groups in like a town of 12,000).
I guess there's at least 3 or more active and currently developed software packages with open source licenses, the flaskbb that site uses, simplemachinesforum, the classic phpbb, probably some others I've forgotten about... The LAMP stack dependencies for all seem very mundane and very lightweight.