If I were to tell you to use all caps when referring to ME, would that be reasonable?
What about all lower case, even when starting a sentence?

Sure. My goddess-mother’s name was fractal, all lowercase. Even at the start of a sentence. Even when yelling in all caps. It was easy to do and made them happy.

Valuing the rules of grammar over people’s feelings seems like a very unusual choice. Personally, I think language should exist to help people, not the other way around.

I use capitalised pronouns because I like them. That’s what the article explains. The reasons that people like their preferred pronouns don’t tend to go any deeper than that.

Maybe a story will feel more complete: 4 years ago, while My goddess-mother was helping Me understand My gender, She suggested I try out capitalised pronouns. I did, and I liked them. As good as she/her felt compared to using he/him, that’s how They/Them felt compared to she/her. I liked them, so I kept them.

Here’s an explanation of My pronouns: https://medium.com/@viridiangrail/introduction-to-capitalised-pronouns-f5140e722b48