Elo decay is a problem in high elo
Tons of people are quitting for one reason or another. The quality of the game has gone down quite significantly, and dynamic queue is another big problem.
However, high elo players are still obligated to play one game a month in order to not decay. They are uninspired, not playing to win, don't even care if they win or lose, and most of the time just want it to be over fast so they can get their month-off again. It happens quite often (and these people are quite open about it as well) that one of these players is in the game on either team, and it's just one more factor leading to shit games. People are quitting the game and the decay is causing them to ruin games for people who are still playing. That's not cool at all.
I don't have a solution. But this is a real problem especially recently with how many Diamond players have quit playing Ranked.