You are right. Players are allowed to opt out and have standards. That is not controversial. Your issue is your framing and the sneering.
I bolded some clearly mocking phrases. Why are you mocking DMs? Once we start mocking the DMs, we stop having a neutral opt out, and instead we have an opt out while sneering. There is a real possibility, that DMs aren't snowflakes, but simply don't care for the opinions of players who opt out of their game. Why would they care, they are there for their own fun. I know for my private games, I could care less what you or anyone not at the table thinks.
The WotC comparison is incorrect. WotC products are commercial goods sold to a mass audience. A DM’s campaign is a private, unpaid creative offer to a small group. It is very different to criticize a commercial product, than to criticize someone's private fun you are not a part of. You are doing the latter, and doing it on a broad scale.
You can believe what you believe, but when you use the tone you are using about a community, expect social friction. I can say “System X isn’t for me,” and the reaction is very different from me saying, “System X is lazy garbage and anyone who likes it has low standards.” One is a difference of opinion, the other is elitism in it's purest form.
So I think we should not broadly insult wide swaths of the community, because we disagree with their fun. But who knows, maybe that is a lazy opinion to have.