This is a bit much, tbh.
Punishments should be made to fit the crime.
Here’s some simple math:
If someone leaves RSS, they should be punished with a CR & MMR decrease and an account-wide timeout from queueing rated.
Let’s say avg dps queue is 30 minutes.
Let’s say healer queue is instant so it’s immaterial.
There are three other DPS in addition to the leaver.
So, that’s 1.5 hours that the leaver wasted for those three other people. Now, they’ll have to collectively sit another 1.5 hours in queue to get another game, and in that game they might gain / lose CR.
So, three hour account-wide timeout for the leaver.
This would be more reasonable