Is Amazon hiring existing members of the Rust Foundation such that they weren't involved with Amazon but now are? e.g. paying these people to work on Rust but under Amazon's terms?
Isn't it then up to the Rust Foundation to declare this a conflict of interest, perhaps, and to sever ties with that member?
That said, Mozilla really did drop the ball by laying off all their staff on the Rust project and effectively defunding it. They might have well have created a power vacuum and Amazon beat Microsoft to the punch.