The most disappointing thing to me about alt-text discourse isn't that people aren't putting alt-text on their images.
It's when I see people talking about it dismissively, framing an expectation of alt-text as "policing", or as if it is some bizarre request with no practical purpose, some demand that people make just so they can be difficult about something - not even *entertaining* the possibility that maybe people have a very good reason for expecting it, and there's something to be learned from it.
Related gripe: people *seriously* need to learn to deal with criticism in a healthy way.
Yes, you are sometimes going to be told "no". You are sometimes going to be told that something is expected of you that you don't like, if you want to participate in a community. You will sometimes get an unfriendly or hostile response if you wrong someone in some way.
These are normal parts of life, normal products of social interaction between people with different backgrounds. What's *not* normal is expecting every single word uttered to you by someone else to be friendly or polite, or to always get the benefit of the doubt.
@Mikal
I saw one like that recently. The OP had used auto generated alt text, which was slightly incorrect. 
Someone pointed out the mistake.
Instead of the OP saying "thanks, I'll update that" they went on a rant and blocked the account that pointed it out. 
Total overreaction I felt. 
Yes, we prefer good vibes for making the effort, but no need to have a total meltdown when someone points out a chance to improve it.
🙃
And I see this in so many other places too. There's very little that gets you framed as a dishonest person faster than showing empathy towards people you don't (all) personally know.
And that is fucking depressing and, IMO, an indictment of everyone engaging in that kind of dismissive behaviour.