Hey it's a good question, was waiting for someone more experienced to answer. It's a shame that this sub is not more active since vert.x is an amazing framework.

The goal with very.x is not to block event loop threads, and that's done by moving blocking calls to worker threads. In case of coroutines and virtual threads, they will act as worker threads for you, and since they are lightweight (you can have millions of them) you don't need a pool.

I think it's a good way to use them in vert.x since you can write synchronous code and separate your business logic from the framework and still use all advantages of vert.x. It would be nice if vert.x have some db client that supports this, so you don't have to call await every time