There are a lot of glaring issues with BfA M+ dungeons. It's Cataclysm syndrome where they decided they wanted to take a system people liked and make it harder in unenjoyable ways.
Frontal mechanics for instance. There were only a few in Legion and they were basically all from large mobs where there were only a few in the entire dungeon, the naga casters in Vault for instance that had a frontal silence. BfA dungeons have a ton of mobs like this, mobs with small models that you literally cannot even fucking see which way they are facing when you have a few people hitting them + other mobs in the pull. The maggots in Underrot, like half the trash before the third boss in MOTHERLODE, etc. And there is no room anywhere in said dungeons to move the pulls to so you can maneuver.
But the biggest, most glaring issue with BfA dungeons is the amount of trash and inability to skip most of it if you don't have a rogue. If you use Mythic Dungeon Tools to build routes for the dungeon you are running beforehand you will see that if you do not have a Rogue and thus cannot do any shroud skips you will be well over the needed mob count in pretty much every single BfA dungeon. This is ridiculous because the timers are already much tighter, with much harder trash than anything in Legion. This is the single biggest fun killer, for me at least, in BfA. They need to remove trash and give us options other than "bring a rogue".