It's good because it gets better players out of the ranks they don't belong in faster.

Nobody likes getting stomped by a diamond player in silver games.

I spent 3 seasons goofing off with friends in low silver when I previously played in diamond. (No money for different account)

Those friends have moved on from the game so I climbed back up from silver.

To be honest I felt bad for a lot of the enemies I was against. A lot of the games I would get flamed for smurfing and how it ruins games.

With a maintained 75+% win rate on dps I blew through gold extremely quickly, gaining sometimes 60-70 sr per game.

I believe that is due to performance based sr. It let me get out of their games quickly and back to similarly skilled players.

Obviously this is an extreme example, but the concept is the same across the board. Let the players who are obviously stomping climb faster so they stop ruining people's fun by stomping.