The reason they made shove a bonus action, as I understand it, is to give martials more to do than just whack. So if they were to balance shove to be a replacement of a weapon attack, that would be a problem again. The current solutions to what they're trying to fix are huge problems to the 5e balance.
I actually agree with you entirely that it's not necessary, but I'm trying to come up with a compromise to keep everyone happy. A solution that wouldn't mess up the balance of 5e so much.
