They should probably change their terminology away from "RFC" for referring to Rust RFCs rather than IETF ones. Maybe RRFCs or REPs something?
In this document is a perfect example of the problem, they list several Rust RFCs by RFC number, then talk about IP RFC based loopback detection, expecting everyone to know that RFC 6890 refers to an IETF one and not a Rust one. I mean, most of us can infer that just by length of the number, but it is pretty ambiguous especially when they're used in the same document like this.
I have the same thought running through my head while perusing each Rust announcement. Python has the Python Enhancement Proposal[1], and Bitcoin has their Bitcoin Improvement Proposal[2]. On the flip side, this does have the side effect of forcing me to click through to each Rust RFC linked in the announcements just to be sure.