Rosetta 2 could serve as a crutch for developers that don't want to expend the time and effort updating their apps to native ARM compiles. As such, those apps will perform more poorly than they would otherwise. Of course, that needs to be balanced against the potential lack of that app entirely if Rosetta 2 is removed. Looking back, Apple seems to lean towards the more harsh scenario. I am guessing it will be removed some time distant in the future.