I appreciate that you broke apart the users into two groups. I imagine Group B is much larger than Group A, and that the Haskell maintainers want to emphasize "if you use accursedUnutterablePerformIO, make sure you are in Group A!".

Most Group A people didn't get there fixing surface level stuff. They got there because there was an insidious defect buried deep that required that deep knowledge to understand or fix.