Difficulty settings are, first and foremost, accessibility settings.

I have to disagree with this. Difficulty settings are at best a bandaid solution to accessibility. The vast vast majority of difficulty settings change the overall gameplay experience, games are far too complex for ‘just make it easier’ to be an appropriate approach to accessibility.

Just reducing enemy health, simplifying enemy ai, etc. can only make a game more accessible as a side effect, it doesn’t address the actual accessibility issues people might have.

I also don’t think games should have hard modes. They should have exactly 1 difficulty the developers balance around.

There absolutely should be accessibility options that have the side effect of making the game easier but making the game easier is the wrong approach to make it accessible.

My suggestion would be stuff like tuning response windows to the results of a reaction time test, aim assist options, visual cues for sound effects, etc. Those make the game easier but do it by addressing a single specific issue, or combination of issues, someone’s dealing with instead of just slapping on a one size fits all solution.