To be fair, a fighting game being simplified isn't as bad as simplifying an MMO.
In a fighting game, you do still have the unpredictability of your opponents that comes with being a PvP game. As long as they don't remove the skill ceiling with niche stuff you can do to counter, it's totally fine to make the game more accessible.
However, in an MMO, you fight a script, it never deviates, it's never unpredictable, it's always the same. In that scenario, if you make the way you play also always the same, you turn hard content into nothing but memorisation. The only challenge is how much information your brain can retain (which is also why 3rd party assist tools are on the rise, it alleviates cognitive load by having a machine tell you what to do).
Honestly speaking, if the fights were entirely random and unpredictable, the current kits might not be as bad, but given that everything is on a script, sanding down job gameplay is unacceptable.