Ok, so while some stuff was altered for the worse throughout Legion, most classes still retained interactions which increased rotational complexity through artifact abilities and legendaries where BfA largely keeps the overall feel of those rotations while simultaneously removing elements which had previously allowed for skill variations.
That's not to say that skill was no longer important because obviously you still need to perform your rotation as close to flawlessly as possible while dealing with mechanics effectively, but the rotations themselves across the board lack the depth that Legion allowed.
To give an example just from my own experience as a Mage main in Legion, stuff like double ice lance in its pre-nerf state, or the prolonging Thermal Void minigame were things that had a very high skillcap, but in the grand scheme of things only added on a couple of percentage points at the top-end beyond performing the rotation without necessarily planning ahead, or having to constantly reposition while avoiding fire and tracking haste percentages for shimmerlance, which in itself uses a charge of a defensive tool and carries a risk. Sure, BfA Frost feels very similar to Legion Frost, but it demonstrably is not.
That's kind of my point. It's more or less the same, but very much on the less side of that equation for a few key reasons.