Call them anything you want, as long as people understand that you’re talking specifically about those people who are living on the land as defined in the Oslo Accords - because that’s what everyone knows as Palestinians.
You could call them Muslims, but there are Muslims in other countries, so that doesn’t narrow it down to “that group”. You could call them “terrorists” - but there are terrorists inside the USA, inside Europe, inside Syria, inside Afghanistan ... so that doesn’t narrow it down to that specific group. You could call them Arabs, but there are Arabs outside that area, so again, it doesn’t narrow down to that specific group.
You could call them the X-People, and you could give the definition that would narrow it down to just them, but would anyone else know what you’re talking about. It’s not likely - so it would be a non-useful word.
That’s the kind of problem you have with whatever “word” you choose.
How about we call them Syrians, Egyptians, Jordanians, and Lebanese because that is what they are.