The new winions are no fun
In one of the last few games I played, we had an Alistar who ragequitted at level 3, but despite it being a 4v5 we were still ahead. We were winning teamfights early, getting objectives, but after a few teamfights we found that our turrets were dying due to minions. This forced us to go defend our lanes, which in turn gave the enemy team the advantage as they could grab objectives with no worries. We even had minions pushed up to their nexus turrets, but they were just stuck there due to the level advantage, and we lost still ahead in kills and dragons.
This new winion mechanic is not the comeback mechanic that Riot calls it; instead it turns games into stompfests and just makes the game less fun in general.