Yes indee, they "solve" a problem wich can be solved much easier and at much less cost with a centralized database. So, frankly, the tech is useless.
Therefore, sooner or later they will probably loose all their users. At leat they will loose like stocks, bonds, real eastate, etc. in value against #bitcoin.

For me, they are just nothing else than an evolved form a stock. That's fine but everyone should know what he or she is doing.