Yes bitcoin is a cryptocurrency which is created to serve as a payment method but first and foremost important thing is programming and developing it. As you mentioned Ethereum has more use cases and can be served as a platform for dApp creation, the same thing applies to eth and all other crypto as well, first it needs a good programming, developing and research team, then it can be used as payment method, assets, dApp platform or any other use case.
No. I am not talking about developing. I mean what bitcoin can be used for. For most people, Bitcoin is a good asset and collection.