i started using the internet in the late 2000’s and still remember when you search for something most of the times it would return with a forum post … now its just random websites … if you ever need real and concise answer you have to add site:reddit.com at every search and since discord or twitter are not crawlable by these search crawlers they are not mentioned . Where did all those forums went…are there still active forums ?
People hosted their own forums as there was no viable alternative, and you didn’t care about legal liabilities, data governance, right to be forgotten, DDoS protection etc.
Most people (not all) will choose the easy option of an existing service. Of which the value for that service is to lock you in and spend all your time there.
Saying that I’m still active on multiple forums, but they’ve been around for years, and it’s definitely an older nerdier demographic.