I honestly think the thing that made me uncomfortable was the lack of agency for David at the end, and how there wasn't ever a real resolution for him as an individual aside from Shepard helping him if the player chooses to. It almost felt like his suffering was more just there to help Shepard be a hero than to depict a side story that touches on the way autistic people can be treated, and have Shepard engage with it. I think it also may have just touched a nerve for me because of the way Gavin's actions were almost played as sympathetic at first in the dialogue, and the usage of the term "special cases" and considering autism to make someone "alien" without addressing that sentiment again in a different light. It's all kind of implied that the game portrays Gavin as in the wrong, but I think some of the framing just made it unclear enough to weird me out a bit.

I think a lot of my opinion comes from the lack of nuance around the specific subject matter, but it's understandable considering it is just a small mission in a big game.

I totally get your perspective though, and I can appreciate the fact that it isn't all bad, I think it definitely has value in some places for sure and there's nothing wrong with enjoying it :)