signs that things might not be that easy, i'd say that the answer is rather "actix-web". axum has tokio's momentum, but a much shorter track record than actix.
For me Axum should be the default recommendation because it's the least quirky option. It's also a very thin layer on top of hyper, and built by the tokio team, both of which have a very long track record.
Actix-web is a fine choice, but it's a bit of an odd duck in things like not being based on hyper, which makes it a little harder to integrate with the rest of the ecosystem.
Axum is very young (was announced <1y ago), it has good momentum, is based on hyper and built by the tokio team. On the other hand, it has few actual projects built with it, I couldn't find a guide for it like actix or even Rocket have (it has some documentation in its docsrs documentation, but it is pretty minimal). Crucial questions like how to handle configuration, integration with database, autoreload, are left to the examples at best.
I have no doubt that these things will come if the framework matures. I'm just questioning if it should be the default choice right now, as opposed to in a year.
(Btw, I would absolutely recommend against Rocket right now, even though API wise it clicked the best with me, until it gets more maintainers and development resumes)