Sports-related message boards are another example of "old internet". These boards were usually set up in the 2000s and managed to survive the social media era due to the common culture shared by its users that kept them from moving to Twitter or FB groups. That led to a dilution of community on those larger social media groups, because with each viral post, they'd attract a huge number of new users who would change the culture, but dint of their size relative to the original tribe.
Paradoxically, this also kept the messageboard membership small, as users had to set up an account to post. It wasn't like FB, Twitter or Reddit where one account gives you a passport to post and comment nearly everywhere.
I've posted more about old message boards and culture on my personal website [0]:
[0] https://fuzzcrush.xyz/blog/dead-forums-extinct-communities-a...