I am a straight man. I started high school in 1982 and finished college in 1990. I believe that my personal development would have been very different if I had been gay. I think this would have been the case because I would have been forced to deal with society from the point of view of an outsider even more than I already had to.
As adolescents develop, they are trying to find an identity. They typically want to be accepted by their peers and by society as a whole. They may want to be unique, but they typically do not want to be so unique that no one can understand and relate to them. I believe that this set of desires would make it much harder to develop (all other things being equal) as a gay person than as a straight person.
I, personally, had some difficulties in my development because I felt I was an outsider. I was an American growing up outside America. Therefore, I did not completely fit in with the people of the place where I was raised. However, since I lived outside the country from the time I was two years old, I was also not truly 100% American in my attitudes when I came to this country to attend boarding school in high school and to attend college. Feeling like an outsider, I often felt that I could not get people to accept me as much as I wanted them to.
I would surmise that growing up gay would have been like this only much harder. As it was, I was different. If I had been gay, I would have been seen as worse, not just as different. It is different now to a great degree, but back then, there was a real stigma to being gay. I would have had a much harder time developing into a secure person who could feel adequate and competent. I think that this would have made my personal development more difficult.