Of course they knew that unless they haven’t done any test at all. Even I knew that just by reading the patch notes before PTR started:
You forgot the super-Diablo in S19? and breathe lightning in S21 can be reflected by monster because it is projectile.
I think dev tried to add some kind of drawbacks into seasonal themes, so that they aren’t just brain-less buff.
At least, HC players can choose not touching shrine/pylon this season. Actually they can if they are careful enough and don’t wear Nemesis.