There are two factors to consider. The first is that up until very recently, being gay or lesbian or trans usually meant facing intense discrimination. You could be arrested, sent to prison, tortured in camps (called conversion therapy), fired from your work, denied health care, or exiled by your family. In many places, this is still happening.
This is bound to cause some stress, depression, and anxiety in someone. Secondly, the way to deal with this systematic persecution and oppression has traditionally been to hide your identity. To live two lives. Your public life, which conforms to societal expectations, and private life. Your true self. The term in American English is to live ‘in the closet. This has also been shown to cause immense psychological damage.
If anything, given all that we have had to endure for so many years, I am amazed that so many of us are so healthy, so optimistic, and so well-adjusted. That so many of us have found true life partners and built loving, stable family relationships. It is a sign that the human spirit is so strong.