She should start using tempered glass screen protectors.
Anyway my cousin has an iPhone with the latest iOS and it's hard to do anything without a PC. It's impossible to install apps from third-party sources (and if you use a PC you can only keep the app for a week, then you have to reinstall it), some Telegram bots are disabled on iOS due to "copyright infringement", some apps don't even parse their own links correctly (e.g. opening a Google Photo link from Telegram opens the browser instead of the app, and tapping "Open in app" always opens the App Store, while on Android it just opens the album in the app), and of course, storing files is practically impossible (even downloading files).
Why pay more for less?
P.S.: iPhones slow down significantly over time, due to iOS updates (which can't be reverted) and the battery degradation being compensated.