Yeah it’s quite unfortunate with iOS. I’m on android but afaik iOS just doesn’t support all the PWA features.
Which is super interesting in its own right, because when you look back at the first iPhone, Steve Jobs actually announced at first that it wouldn’t have a Software Development Kit for native apps and all applications will be web based. They obviously didn’t stay on that path, but I find it quite ironic.
A fork is effectively your own repo, so you can do with that as you please. Afaik MIT license doesn’t hinder you from removing anything.