> We can solve the scalability problems of blockchain. The thing that keeps me up at night is not scalability, it is user adoption beyond the use cases which Bitcoin already successfully fulfills.

Fair point. But none of the biggest chains right now are nearly as scalable as using something like AWS or Azure or Google Cloud. Unless they are able to handle the same amount of traffic, there is no reason for someone to use them for typical applications.

On the development side it will be more cumbersome to develop for, and on the user side it will be slower and/or more costly to use.