[AlexITC]

While the tooling isn't perfect, it has improved considerably over the last years, I remember when IntelliJ couldn't deal with Scala 3 but now, it rarely complains.

Related to Python 2->3, I don't see how Scala 2->3 compares, there are clear migration guides + tools to help re-writing to switch between the new/old syntax, I have done many migrations and I have used these tools since the time when Scala 3 was launched (I admit that I reverted a migration at that time).