I'd rather not put words in anyone's mouth, sorry! It's not like it even matters all that much, it's something that individual project teams could easily fix by improving and standardizing on how to more consistently seek outside community input on new developments (leveraging, e.g. the public 'internals' forum, and/or the RFC github repo). This was not needed before since the core team was picking up a lot of that slack. But obviously we've been seeing some changes wrt. that.
The individual sub-teams have been using RFCs as the way to push through major changes for years and years and years. Pretty much since the sub-teams were born, around when Rust 1.0 was released in 2015. Nothing has changed there. I know because I was there in the beginning and I'm still here.
What has changed since the beginning is that there are more working groups these days. For example, there are working groups specializing in SIMD and error handling, among many others (they just happen to be the ones I follow in particular). The working groups generally work toward writing an RFC for the broader community to give feedback on. But working groups themselves are open to anyone, and they aren't difficult to join. (And you don't even need to "join" to participate. You just have to show up and start giving feedback.) The key point here is that the RFC process is still used, same as it always has been.
To be clear, working groups and the Rust teams choose their own membership. Neither Amazon nor the Rust Foundation have any say.
Can you elaborate? IME Rust development is as transparent as ever.