And if you think people are terrified of messing up the iPhone itself, they cower in mortal fear at trying to do anything in iTunes, which is still, a decade on, inexplicably the only way to do many things with an iPhone (like, for instance, back it up if you don't trust your personal info to iCloud...)
All devices need a universal undo so you can change something and easily undo if you get it wrong or you just preferred the old setting.
For security you could prompt after a while to make the new settings permanent and delete the snapshot.