In my experience not well accepted at all... IF wearing a sign "I'm non- binary".
(A lot of people would think it's some computer problem... you got – a virus?)
Now say, presenting like a guy, mustachio, and wearing a dress might do, in place of that sign though.
Biker leathers with a pink tutu, a full beard and wearing lipstick... seen that... some acceptance issues there to be sure.
But seriously, I'm XY, have a vj, boobs, and am a Monarchist... now... ... none of any of that is immediately apparent (hardly my boobs)... so?
If you don't advertise your being non-binary, I guess there be little acceptance issues.
In fact I have never knowingly met any real 'non-binary' in all my life – yet.
So... not a problem, or?
Axélle