Why doesn't GF bring back the old Hyper Beam mechanics?

In case you don't know, first gen hyper beam did not have to recharge if you KO'd somebody on the same turn that you used it.

So? It wouldn't even be that good due to the normal typing. Worst case scenario a few revenge killers in the lower tiers get bumped to OU/UU along with Porygon-Z.

If they are concerned about in-game balance, remove it as a TM and have a tutor teach it to your pokemon for some expensive price.