idk, I haven't gotten the impression Akira's mother is like, inherently dismissing them. Akira has been wishy washy on the experience so far (and understandably so), at this point I don't think it's clear to them how they want to identify yet. There's still a part of them that's clinging to their past identity as a boy, whether that's just because it was all they've ever known and therefore is "easier" or because they genuinely want to go back I can't really tell, but it's obvious they're not 100% on board with being a girl at this point in the story. They're certainly coming around to the idea and showing interest in exploring it, but these inner thoughts aren't being conveyed as clearly to their parents as they are to us as the reader.
I think mom is just trying to be supportive with the mindset that she thinks Akira wants to be a boy and be treated as a boy but has to do "girly" things for the sake of fitting in and not having a terrible experience like they did at the last school. She could turn around and show her true colors later on in the series, but as of right now I don't get the vibes mom is being malicious, she just doesn't know the full story like we do.