There are ways to fix this, Blizzard even have them in built into the game, and I don’t mean the M+ rating system. But the combat logs we use, they are built into the game, Blizzard just need to implement them the same way warcraftlogs use them in the same way they made an IO system of their own, so we can see now only what your rating is, but at a glance can see how many runs you left, what kind of DPS or HPS we are dealing with. And I am sure there is some details for tanks like damage mitigated, self healing and whatever we may find useful.
If Blizzard just keep a rating system than 99% sure the bar will get set high enough that no one will even be able to pug without providing their own logs, and people don’t log, not really, not until you hit those high keys to begin with, or when we do casual guild raid clears for bragging rights.