Because it's my favorite season, I like the sound, and it's unpopular.
I'd say in the US that Autumn is too popular. It just baffles me that it's more popular than, say, Mary.
Haven't met any. I sorta knew a mtf trans person who changed her name to Winter, but then she changed it to Beverly
Um I don't really like any alternative spellings. I can get behind Wynter, maybe?
No idea! Probably because of the popularity of the Au sound with Aubrey and whatnot? Summer maybe sounds a little 80s or something? Winter is too goth.