Assuming this stabilization actually does happen, whether it happens in public or private is irrelevant.
What matters is that we've seen C++ stabilize. We've seen Go stabilize. We've seen Scala stabilize. And now we'll likely see Swift stabilize, well before Rust does. They are all serious competitors to Rust.
As these other languages continue to evolve, but at the same time remaining usable, the relevance of Rust will continually decrease. It may still have drawing power today. A few years from now, it will have less appeal.