I don't see Black Cat with this group, do you? I'm sorry but saying "Black Cat" isn't a shield to be used to protect against criticism. Felicia's great, but she isn't a Spider. (Also, there can be more than one LGBT character in a franchise. Bluebird isn't the only LGBT member of the Bat-Family.)
Spider-Man is the biggest IP that Marvel owns. The fact that the closest thing to a major LGBT Spider is Ultimate Jessica Drew? A character who has never headlined her own title and hasn't appeared in years and is the variant to another character with the same name? Not a great look.
The rest of Marvel is irrelevant to this conversation. Because this is a discussion about Spider-Man/the Spider-Verse. There are a lot of people who only care about Spider-Man/the Spider-Verse.
(As for Stan being against Peter being LGBT, nobody thinks that Peter will be revealed as LGBT. Marvel themselves have that in their contract with Sony that Peter can only be a straight white male.)