So if the farmers didn't grow glysophate resistant corn instead they would grow non-GMO wheat and spray it with "selective" herbicides that kill wild oats and broadleaf plants over those acres and society would be better.. how exactly?

Roundup is a lot cheaper than Axial Extreme + MCPA or Velocity M3 or Tandem or Rexade.. and, TBH, Roundup isn't tha good at killing a lot of the weeds that those other products kill very well. It's just not as simple as you might think.