https://en.wikipedia.org/wiki/Pale_Fire#Interpretations fascinating takes.
The Botkin theory is very plausible, and these critical essays from Boyd on the Nabokov mailing list is also a fun read (i’m on 3 of 9, made possible by reader mode in my browser, the archive newlines are a little weird).
(you know you are reading some real lore when you see the old “name-l” listserve decorator)