I agree, fight is extremely black and white in terms of difficulty. Either you know it and it's easy or its very hard.
It's very difficult to make medium level difficulty especially midcore content.
If fights are designed a little easier than veteren players will be bored coz similiar mechanics were found in o11s or tea or Eden. So they have to come up with new types of mechanics and if not innovative enuf they have to create body checks (8 players alive).
Savage is evolving to the point where many are getting discouraged from it. Ff14 doesn't do a good job to teach newer players how to savage.
Compared to wow, they have 4 levels of difficulty per raid tier. Raid finder/normal/heroic and mythic.
Since you gradually work your way up the muscle memory sets in and it's not too overwhelming for players.