Rust 1.75 will make both [RPITIT](https://rust-lang.github.io/rfcs/3425-return-position-impl-trait-in-traits.html) and [AFIT](https://rust-lang.github.io/rfcs/3185-static-async-fn-in-trait.html) stable. It's a great improvement for us to reduce the maintain burden and remove a lot of hand writing `poll_xxx` API. How about bumping MSRV to 1.75 in our next release once it's ready?
