Scala 3 slowed us down?

It never went away. It only got more:

https://business4s.org/scala-adoption-tracker/

I don't see the chart with changes of number of companies using Scala over time. But even without the chart - if after 15 years there are less than 300 companies in total, that's a bit depressing.

Of course legacy never goes away, and even 20 years down the line there will still be some demand for Scala programmers. Similar to how Cobol still lives on. But in my experience the language isn't growing anymore, even slowly dwindling in userbase. And this became way worse after Scala 3 mess.

The point was to show that big corps are dependent on Scala, often at their core.

Scala is likely not for everybody, but where you need to write safe high level code there is more or less no alternative, not even on the horizon. Scala is simply very likely where Rust will end up after the honeymoon, when people realize that feature rich, safety first languages aren't for the mass market, where mostly only the cost of initial development counts.

But safety is not the only important aspect of a programming language. For me personally the community (libraries, tools, forums, blogs, etc) became much more important over the years, and I feel that Scala 3 really hurt the community angle.