These products are built purely on trust. These things do not have any innate value. More than that, there is nobody that can be trusted that guarantees the value of it.
Now think about long term stability of something that has value built purely on sentiment and the sentiment changes over time in waves thanks to globalisation.
It is just a matter of time until people, for one reason or another, will get themselves into a spiral where the thing losing value will cause people to loose more trust, causing the value to drop. And there is nothing to stop it except large institutions that have power to manipulate market (if you remember Game Stop saga you know what I mean).
A normal, tangible thing like a company that is profitable and has some future will see ups and downs as the sentiment changes, but the shares will always have some value because not all investors are completely irrational and some investors can calculate the value and at some point will say "Fuck all those people selling it, I think they are all mistaken because I can actually calculate the value of it and the shares are now cheaper than they should be so I am buying".
This should be enough for the instrument to weather even very negative but temporary sentiment.
But this is not true for crypto. Crypto does not have innate value and when it goes crashing down it can easily crash to zero.
Over long time, without giant institutional investors propping it up constantly, it is guaranteed that it will happen at some point.