As someone who believes in social justice, I believe I also have a responsibility to question and to point out some of the issues I see in social justice circles as well.
The problem with ally is that it's an often self bestowed title and not everyone who takes up the title actually is interested in being an ally. An ally is typically someone who is privileged in an area, say a able bodied person who supports the fight to make places accessible.
Being an ally is about supporting the fight for equal rights for everyone in areas where you are generally privileged. It's about supporting our voices, it's accepting a responsibility to educate those of your privileged group when you can. It's about supporting not supplanting.
What it is not:
It is not about talking over our voices. If nobody can hear the minority for all the allies, then you are doing it wrong.
It is not the right to police the voices speaking up. I should not have prove to you I am autistic before you will allow me to speak on my behalf.
It is not the right to hijack our fight or to bully others in the name of being an ally for your own amusement. Also, it is not the right to hijack our anger, as frustrated as you may get trying to educate people? You don't have to put up with the reality of the bigotry we face, learn some patience.
It is not the right to deny rights or voices to people of our group who you decide aren't part of it, or you dislike, or who you think should be an exception. I have seen people declare themselves allies to survivors, talk about how important it is to believe survivors, then proceed to belittle and attack someone who apparently was "lying" just because the so-called allies didn't like them. Support all of it, or don't call yourself an ally.
It is not about getting a "cookie".
It is not about being seen as a "good person".
If you do any of the what it is not list? You are no ally to me or to anything other than your ego. That behaviour is toxic.