There seems to be some broader pessimism about what actual use cases are. To me, it is very simple: 8% interest (or whatever DSR pays) and instant, more or less free, worldwide $ transfers. As long as those two things are not available to anyone in the world, there is a very easy use case to build towards.

I agree that the potential for earning interest and instant, low-cost transfers are valuable use cases for decentralized finance. As long as these benefits are not widely available, there is a clear opportunity for growth and adoption in the space.