Yes, but there were only a few people around and they were tech savvy and often entrepreneural especially in tech forums... Now when a forum gets any sort of uptake, it is jumped on by marketers and other spammers. So elitist, I guess but it was automatically back then I guess.
Good moderation feels like a better solution than invites or elitism here. Have the forum open to anyone, but be ruthless when it comes to removing low quality content or marketing spam in any form. Maybe even set things like signature links or certain aspects of the post formatting to be only accessible to those with 5 or more posts, and have any first post with a link in sent for moderator approval.
Human moderation always wins out over technical solutions and elitism.
Not to mention the social shaming of people trying to sell things is always pretty scathing on forums. In general they tended to promote good content by liberal application of both the carrot and the stick. No one wants their product associated with a 17 page thread about how product X is sold by a bunch of annoying spammers, oh and by the way for anyone interested, turns out CEO of the company shilling this product has a kink.com account looking for a strong domme in the SF area to punish him :thinking_emoji:
Free for a heavily selected group of people with internet access and specialist knowledge of how to find stuff. So: elitist in a sense of resources weighted by interest.