Facebook, Twitter, SnapChat, InstaGram, take your pick - they're "social media darlings of the moment" - and so far (in the Internet Age), there have been a total of ZERO "darlings" that have lasted...
Remember, Facebook replaced MySpace which replaced GeoCities... The brilliance of some of these site owners has been the ability to monetize and capitalize on these "properties" so quickly!
There will be a replacement for Facebook eventually - and Twiter, and the rest - it's just a matter of time. The best part is that it only takes a few $thousand to start up a new app - the expense comes when you need to expand and grow! But the tech has never been the hard part - getting people to USE it is the hard part!
Ask Parler... or DOZENS of other would-be social media "darlings" - it doesn't take money or tech to succeed (though some of both ARE required), rather it takes "magic" - the "magic" of being at the right place at the right time to "catch fire"...
Even Donald Trump couldn't create that "spark" for his own "Trump Social" - and it's (so far) falling flat! But then Facebook didn't start out "on top" either!
If you can predict the future, which one will you bet your own money on???
(Or, I choose badly - but then it would be my own fault, and we can't have that!)