Adults, on account of daily experience having a vanishing small impact on accumulated experience, do not change personality or attitudes very quickly. They're almost set in stone. Plus learning to deal with one adult is a transferable skill to dealing with another because adults have all learned more or less how to also deal with each other in spite of differences.
Adults can be very forgiving about your mistakes because they know you're learning and you aren't perfect. This gives you confidence to make mistakes and try new things so you can get it right more often.
Meanwhile children, especially teens, are still learning to human, their patterns of behaviour change week to week or month to month. If you treat a teen the same way you did a year before they don't have the social experience to handle that with grace, which makes additional social friction for people who like to find a solution that works for them and not adapt it any more than the bare minimum for extended periods of time.
Teens will take every mistake as an insult or make fun of you for it no matter how small the mistake which can make learning harder and slow your progress to finding good patterns of behaviour that work for the people you're trying to communicate with.
So the skills you developed before you started school to interact with adults and have tweaked slowly for 13-14 years with millions of tiny interactions and experiences are well developed and stable and you know what to expect.
But the skills you developed for dealing with teenagers which have changed dramatically from being a toddler thinking they were essentially adults, to a little kid where they were fun, to a bigger kid and they became scary, to a teen yourself where they're your peers haven't had the time or experience to be as comfortable to you.
You may only have 3 or 4 years of skills development, and most of that has been adapting to your one or two close friends who're willing to forgive more of the mistakes you make than average.
Meanwhile your skills for half your class might fall back on patterns you developed for those individuals at 6-10 before the hormones attacked and messed up everyone's brains, yours included. So off hand you might do things that upset them whether or not they make an issue out of it it colours their relationships with you in their heads.
All of this means you're going to extra struggle with interacting with peers more than adults, and no this doesn't just apply to ND people it applies to everyone, this is the whole process for growing up. However my experience is such that the pain and embarrassment of getting it wrong doesn't weigh as heavily on NT people as ND folks, they can seemingly take the minor rejection in stride and it not have a crippling effect on their thoughts and actions for months afterwards.
I don't know if this is the whole answer it's certainly not peer reviewed but it is what I worked out for myself and it feels logically consistent with my experiences of the world. It might help you too.
(I posted a version of this in the comments since my queue was long)