Like, thats just being obnoxious to play against.
Like, since everyone and their mother are taking it now, say you win lane but your 3 out of the other 4 players feed hard on your team.
So now not only you have to deal with those players, but you have to deal with super stacked dark harvests that can all be comboed together on you, so you're trying to carry but its impossible since the moment they drop 2 spells on you and proc 3 dark harvests you instantly die, even if you have some hp/armor as a fighter.
Yes, i just had a game like that where i was riven stomping my lane but they had an extremely fed mid, jungle and bot lane, all with dark harvest, if the rune didnt exist i would maybe be able to do something and try to delay the game but nope, im not saying i should be able to win games 1v5 every time but this is literally just a fking keystone taking away any kind of agency you can have in your game.
I think dark harvest should just be completely removed from the game, it does not promote good gameplay and punishes your team mates for feeding too hard (something completely out of your control).