I'm marginally bothered by the reluctance to bite the bullet and accept a 2.0 will happen in the future, but version numbers do not make for mature libraries. There are plenty of foundational libraries written in C keeping Linux desktops running that are permanent 0.x versions.
> Whereas from Scala you can just use any Java library e.g. Vertx, Spring almost all of which have commercial, enterprise support and continue to be proven time and time again.
I find that "wide and storied library ecosystem" can be a double edged sword: an old library can either be battle-tested, or just old (with cruft or poor design or implementation) and you can't always tell which it is ahead of time. This is true for libraries in any language, and the same thing will happen to Rust in 10 years.