Cause Shakespeare wrote his plays in Elizabethan times and women wouldn't be allowed to perform on public stages until the reign of King Charles II so any female roles were performed by men, there were also fairly strong laws regarding sodomy (although in earlier centuries, it was possible for two men of the clergy to form something of a civil union-which was supposed to be non-sexual but in practice was another matter, although I believe that this practice had subsided by Elizabethan times). There were also different societal expectations regarding marriage and family for men and women, which is a large part of what romeo and juliet revolves around, eg Juliet's arranged marriage would just straight up be a non-issue if she was a son. Still, Elizabethan sexuality and how that intersects with queerness is a very interesting topic and I would definitely recommend reading up on queerness in Shakespeare if that's something you have an interest in-Melissa Sanchez has an excellent introductory text on it and Pinaki Roy has some fascinating essays! (For me I always enjoyed Twelth Night, which despite the comphet ending is still pretty gay) (Edited for typo)
