Everybody agrees that Rust's ecosystem is too fragmented, but I don't think that the solution proposed here will solve anything.
The most promising project to solve this problem is https://github.com/rust-stdx/stdx which is (more or less) re-creating Go's standard library in Rust.
While the consumer market is still years away from widespread RISC-V adoption, if you pay attention to the embedded / MCU market (especially Espressif & co) you will indeed come to the conclusion that RISC-V is inevitable and software maturity will probably come from these early adopters.