The first step is to overcome the dependence of the common forum places, being able to renounce to them, remove your profile and learn to enjoy your life without them… only then you can happily drift into a less crowded and active community for ocasional wonders and quality instead of the saturation of engagement that “that” centralised social media offers, the peer pressure to be part of the main stream…
I see, my tip was thinking in meta/tiktok-like socials rather than reddit/stackoverflow-like. But I feel that it is not too much different. Probably the error was pouring so much knowledge in such “volatile” places (in the sense of user/community not really controlling it) in the first place, but aren’t human interactions already like that? Accept them as conversations lost in time, something always survive and returns, and new things always born. A pity, sure, but a part of life. In any case, it is quite unlikely to reach in a new place in barely a few years the same quantity of information than more than a decade of knowledge in old forums, yet I feel that pian piano people contributes to the shift… in the end we are humans which enjoy of social exchanges :D