I am trans. I would put the proportion of trans people at around 0.1%, around 40,000 people in the UK. It's very hard to get figures of how many people actually transition, but I got that from the Government's LGBT survey. Roughly, a tenth of the trans people there surveyed had a gender recognition certificate, so multiply the number of GRCs by ten. It's a very rough guesstimate, but I think I have the order of magnitude right.
One thing I noticed on this thread was people saying the trans women they actually knew seemed alright, but then they read about stuff they found offensive. I worry that one in a thousand people don't have that big an effect on society, but it's the ideas, or the principles, which are winding people up. Caitlyn Jenner offends people, and yes choosing nail colour is not the most difficult part of women's lives, but her life is as unlike mine as it is unlike other women's. She is part of the Kardashian clan, and the attention paid to her, and what she says, is Kardashian more than it is Trans.
Our experiences are different. I am 5'10" and over fifty, so the bloke coming on to me on the bus was irritating rather than scary. It's not the same as for a teenager. And when a bloke shouted "Slut!" at me in the street I was relieved- he was being abusive, but I thought he would be more abusive if he read me as trans. Talking face to face, I think I could probably find a lot of agreement with many people here, but where we go on line polarises us.
And some have met a trans woman they found did not work hard, or was offensive. But we don't all share the worst characteristics of the worst person you've met.
Trans acceptance is extremely important to me. It's my whole life. If we really are one in a thousand, it is less important in the day-to-day lives of others. You won't come across us that often. But people here say they read something, then they discuss it on message boards, and get angry.