That comic at the end perfectly sums up my reaction (mostly because I want GATs though :)).

I'm not fully sold on Rust's existing async/await implementation but how would this suggestion even be implemented? It's a massive breaking change on multiple fronts and I don't know how a new edition would paper over the impedance mismatch between the new system and async libraries written in the older edition. Feels like I need another year or two of using async rust in production to even begin to form an opinion on this.

How would this work on embedded? I haven't done embedded since long before I could use async/await or Rust but it sounds like implicit anything (except maybe autoref/deref) is a deal breaker.