Plenty, they could:
Remove myth track entirely, have hero scale to 12/12.
No more unique CE mounts. Make them recolors of the AotC mount. Ditto KSM/KSL and drop the glad mount to the “Elite” level (1850 iirc?).
If you think about old raids, like Onyxia. Getting the kill was a given if you all showed up and most of you stayed connected. But those with mastery of their craft 3 manned it. It was amazing.
Separating the challenge from the rewards was Vanillas wow shot across the bow for traditional MMO’s. The secret sauce. Elitist Jerks was a meme, people who did all this research and optimization to glean all the dps they possibly could — impressive, but unnecessary. But now, 20 years in and so many people sitting at the skill cap, really all they challenge anyone on is cognitive load and dedication. EJ has taken over the game and you need to do that to even beat it if you want more than a consolation prize.
I’m not saying this is better or worse, just different. But yeah, it could be more casual friendly without giving up the competitive angle, if and only if you give up elitist entitlement.