I mean that's the nature for most online platforms. It's just that the newer ones are made for profit, so they last longer than would fan made communities of forums or irc of eld. One dies we go some place else.
Even platforms like usenet news, and the old Web 1.0 type forums, even though they weren't really run for profit, they got overrun by spam (usenet), or faded through user attrition (forums)