I'm sure it's the same with any LGBT identity considering cis + straight is considered "default" by so many societies, so if you're anything else it's really confusing to grow up without any knowledge that you're actually completely normal. That confusion without clarity often leads to harmful mindsets and behaviours whether it's towards yourself or others. Speaking personally I had a lot of internalized homophobia growing up and it took a while to get it out of me and the reason for that is never seeing another gay person portrayed in a positive light, and that's in the very few times I've even seen gay people portrayed at all.
Lack of representation kills. It's really sad when other LGBT people don't see this.