i start to loose ideas how explain homophobic closeted gay tropes a bit, easier is to make one big post...
OK LET'S STAY BY THAT OKAMA ISLAND, he was at first surprised and, ye, kinda scared that... (praying to my rainbow gods) girls were not how sanji expected them to be, but yet when he got better introduced by it he yet enjoyed his stay there UNTIL there was that newspaper drop what had to shock him out of it and get back to... how to say it- point 0
being mad at himself that he was not there for luffy, as other straw hats, had to push him on more training than getting back of finding himself
there's much more to uncover like for example his exaggerated reactions to usopp pretimeskip where every other guy would brush it off or such, where he acted quite afraid of himself and that usopp was silly around, I talk about grabbing usopp's hand while sleep (can happen to anyone, I mean here his reaction) or when sanji called nami cute and when usopp in jokes asked him if he meant him he lashed at him for that, the most popular examples here.
When someone is overly almost paranoid to show that NO I LIKE GIRLS AND GIRLS ONLY I LOVE GIRLS WOMAN GOOD MAN BAD it just hints that yet someone can be in denial if there's anything else against other people who yet have different preferences (I'm not saying about the most okama okama characters like on the fishman island twins or ivankov, cuz he acted with rather respect to others, like bon clay.
but sure u can read him as straight, I just bring here some examples what could hint something else
everyone has their own hcs but I just wanted to bring on the table some facts there