Scala 3 slowed us down?

It's quite impressive that you can swap out major version from under running application and have just one subtle issue.

The upgrade Scala 2 -> 3 is usually super smooth. The compiler does all the work, you just need to update your build config / dependencies.

The only exception is macros: If you used the experimental Scala 2 macros you need to migrate them to the new system which is completely different.