Does it though? They are many longstanding bugs reported in their compiler repository, and this release doesn't seem to address any of them.

I agree that the stability is quite nice. But there are plenty of areas where the language could use some improvement - for instance, the ergonomics around writing nested Single Page Apps is pretty cumbersome.

Weird not to mention Elm's massive breaking change that killed the project?

Bugs not being fixed is not a feature, it's a bug, and it's certainly not stability, it's just cope.