Now, while I obviously feel that not knowing about horses, and worse, spreading misinformation about horses, is terrible, I do also have to consider what we were robbed of when JGY decided to wear his (very stylish, big fan) hat like that.
Imagine it! With his hair up, as intended by established hat etiquette, we would have gotten to see his scandalously pretty uncovered neck! Just right there on display, for all to see!
Naturally, I include Lan Xichen in "we".
Lan Xichen, wistfully thinking about when he was the only one who got to lay eyes on that pale neck. Lan Xichen's gaze getting caught on the soft little hairs at the nape of Jin Guangyao's neck, trying to escape from their up-do. Oh, the longing to reach out and tuck them back in place! The impossibility! The impropriety of such thoughts!
He would 100% develop an entire fetish about it.
(It's not too late. We can still give him that. We have the power.)