I still think it comes from NT culture and out attempts to adapt.
This is a good point - and we are not the only ones to suffer from it in this respect. NTs themselves can get caught up trying to be a certain way, trying to have a normal, successful life (when everyone really is different, an individual). Sorry, I'm not disagreeing or trying to dampen your point - it's particularly bad for autistics - I just sometimes see the things we have in common with NTs too.
this leads me to wonder, do Autistic people tend to be idealists and perfectionist? Do any of you tend to have an idealistic approach to things?
Also I realised I never really replied to your original question (sorry @Greatshield17): I think yes, I have it in me to want perfection and to be idealistic BUT I don't have it in me to actually achieve those things (though idealism I probably exhibit more than perfectionism). My life has been a series of failures in terms of trying to be the things I thought I 'ought' to be. It's moving towards being okay now because I'm trying to be happy with what I can do - and what I can do is not perfect.