If you're no longer climbing its because the game thinks thats where you belong. It tries to put your SR close to your hidden mmr that it calculates. Notice how everyone in the thread who is complaining about lower gains/higher losses is mentioning that when they reach their season high when this occurs. It's because their SR is above their hidden MMR. If you play enough games at that SR and win the game will think you deserve it. Right now it probably thinks you're too high and is trying to put you back to where it thinks you should be.Nah, it was confirmed by Jeff Kaplan himself. Someone linked another post about it here too when it was happening. I forget which.
Yup. You basically need close to a 60% win rate to maintain your current SR nowadays when before a 45-50% win rate was enough to stabilize and even grow with short win streaks.