It’s a completely different situation compared to Python.

With Scala 2.13/Scala 3 they both compile down to an intermediate format called TASTy which allows binary code to be shared. You don’t get the same binary incompatibilities you do with other languages.

That is why I said it “should” work. There are always some really weird edge cases. My broader point holds true. Scala upgrade is not even close to Python 2/3 debacle