The saving grace with this issue is, it usually only effects healers. They have instant queues, so they can just chalk it up to what it is. It usually only occurs when a dps goes 0-6 or 6-0, both of which are usually well outside the control of the healer.
Getting zero rating isn’t the big issue imo. The big issue is when you get into one of these lobbies, and the system pairs you with someone lower than you and you lose MMR for breaking even, because according to the numbers, you should win more rounds because you are higher rated. Thats the big issue.