Note that the damage of the spell itself is 1d6 to make up for the 1d4 AoE.
Not that I think it shouldn't be changed back - it most definitely should.

There are actually a bunch of other broken things, like I found some gloves (it think it's gloves) that increase the damage of every dart created by Magic Missile by 1d4 psychic (making it (2d4+1)*3 guaranteed damage). Lots of fun mowing down single targets, not so much when I realize that the only reason I'm able to make progress is having OP gear.