Once again, a good article! You're certainly a splendid penguin. Wait...was...splendid on the list? Awesome...um...birdy...outspoken...????
I think a lot of it comes down to what is a reasonable ask. If I say that I go by "Ytrorexindaraxiodrir"--I mean, seriously, who wouldn't want a name like that, you could be a dragon or something!--then I ought not be surprised when people either refuse or try but fail.
I think people get confused by thinking that because in a sense pronouns (and names) are arbitrary, it's easy to choose differently. It's not. That's not how habit works.
So I'm happy to make a best effort, whatever people say. But when I get people's names wrong like 90% of the time, you can't expect my effort to be very good. I won't draw any line. If someone asks for zie/zem, I'll try. I'll just probably fail. (If everyone goes by zie/zem, then I'm good--new habit.)
--Ytrorexindaraxiodrir (us/the)