quarantine 'em

...even if you do know what to change about your writing to make that reader happier, and you CAN, doesn't mean you should Because you can't please everybody

Knowing you can't please everybody means consciously throwing out the reading preferences of most people who could potentially read your thing. Maybe the real problem is that this person was recommended your thing in error

Obviously there's a spectrum of subjectivity here, I mean obvious spelling errors and glaring plot holes (and, on the gaming side, broken mechanics) are pretty hard to argue with, but sometimes you have to plant a flag and say, nah, this is intended, deal

And if the thing they don't like is intended, maybe the solution is to make it clearer that it's intended, not a mistake

I've had people get X chapters into Ra and report "I'm not feeling this, does it change later?" and my response has been "Somewhat, but you can probably stop reading" because I don't stand to gain anything from the alternative

Have you ever noticed that I don't tend to put "(1/n)" on my long threads? That's because I'm just rambling

All of which says nothing of the kind of critic who's impossible to please, or whose mode of criticism is to scan deeply for all varieties of "flaws" and then rank based on the number found, where the best theoretical critical result is a grudging neutral zero

This person's opinions can be discarded. There's nothing to gain from trying to please them. Best you can do is try to ward them off, somehow communicate that you're not playing their game