It all boils down to intolerance with these backwards people. Whether that be through wilful ignorance or lack of education. It is about intolerance and the fact that someone else is different to them and because they don't understand it or don't want to understand it then they choose to be nasty about it. Maybe deep down they are scared?
Like someone who kills spiders in their house because they don't understand the spider and they are scared of the spider. It's not doing anyone any harm. The spider cannot help that it is a spider and that it looks different and it is most probably going about it's daily business of raising a family of spiders, building a home and finding food. Yet when some people encounter one they feel the need to kill it or attack it in some way.
It's the same with people of different sexual orientations maybe in terms of attacking something / someone they are maybe frightened of and don't understand.
Personally speaking i don't understand the complexities behind trans people for example and that is probably through a lack of education on my part and the fact that i've never ever met one in person in 40 years. Obviously they are just people like me but just have a different sexual orientation to what is considered the norm. I wouldn't treat trans people any different to anybody else and nor should anyone else. I might find that i don't have much in common with them but that's the same with a lot of people gay, trans or straight. I wouldn't feel the need to attack them or abuse them or troll them online or even bother them. It's none of my business.
Personally bi-sexuality tests my understanding to the limit as my brain works in absolutes. I don't understand the process behind someone being attracted to men AND women. I'd have to say that if i had any miniscule slither of intolerance to any section of the LGBT community it would be bi sexuals because i don't understand how it can work. I don't understand it. I wouldn't treat bi sexuals any different however. I used to work with a bi sexual man a few years ago and i have to admit i was taken aback and again, because i'd never met a bi sexual person before. Obviously they are just people and haven't got 6 heads and webbed feet but it put me on the back foot as it was new to me.
People should have the right to be treated equally as people / human beings whether they have a disability, a different sexual orientation or even if they think they are a practicing witch and i'd always adhere to that. They aren't doing anything wrong or harming anybody. At the risk of sounding even more intolerant, anyone who disagrees with this is wrong.