In terms of Self ID (and I guess the broader implications such as gender neutral toilets), if you look at the Denton's report for the IGLYO (it's available online if you search for it), some of the suggestions of tactics for lobbying government are:
- Target youth politicians
- Get ahead of the Government agenda and the media story
- Tie your campaign to a more popular reform
- Avoid excessive press coverage and exposure
Obviously these are just guidelines, but it mentions Ireland as one of the countries that has been successful in this regard. It shows a very deliberate, covert lobbying of government to get these measures pushed through.
If you think about the abortion referendum and same sex marriage, these were grass roots campaigns that took years to get any traction in political circles. And even then had rigorous public debate before any vote took place. It's very telling that this issue has had none of that, instead it was very deliberately done out of public view. This is because they know well that the voting public would be very against it.