The accessibility would be improved by minimizing the number of button presses, considering Square Enix has already made the 'what do I press?' part pretty obvious. Just look at MNK, VPR, SMN, PCT, and RPR — all released or reworked recently. Not even BLM was spared.

Personally, I think players should be incentivized to learn, not the opposite. That said, I don't see how this would harm the game any more than the recent job changes have, and I wouldn't be against it, as long as the GCD lock cannot be bypassed by any 3rd party tool.