Gaza is like Egypt because of Egypt's pan-arabist policies, yes.
There are also Bedouin there. Ceetainly were, until recently, but probably still are. The Turkish Gazans have tried to flee to Turkey, as possible, in the current climate, but not sure there's as easy an 'out' for the others like the Bedouin (especially as even the progeny of the "Egyptian diaspora" of officially encouraged post-Palestine policy isn't welcome to Egypt, etc).
The West Bank has Turkish Palestinians, Kurdish Palestinians (I don't know if they get on together better than Turkish Turks and Turkish Kurds and Syrian Kurds who have gone to Turkey) and Assyrian Palestinians and even (apparently) Russian[/] Palestinians, amongst other not-actually-Arab groups.
The strange part is (except, of course, that it stems from extreme Realpolitik) that Iran, overwhelmingly Shia, is the main nation supporting Gaza, overwhelmingly Sunni. Generally you'd expect extreme dislike between the two groups, at the very least at a national level, but "My enemy's enemy..." is probably the clincher.
But there's a lot of difficulty even equating 'Arab' with 'Arabic world', the linguistically 'Arabic' or even ethnically 'Arab' (especially not 'of the Arabic Peninsula') in the clear sense. Iranians would likely wish to identify as Persian, the Kurds as Kurds (probably above being Iraqi, Syrian or Turkish, e.g. for above-noted reasons of conflict and other not-so-old reasons we could mention) and the Azerbaijanis are yet another separation within the "Middle East And North African" mish-mash of multi-continental "Arab states" (not sure if they were ever Arab League, from the days of Pan-Arabism, given their time subsumed within the other post-war bloc involved). Ok, so they're maybe more homogenous than the "BRICS" group (from the original five, India is notably lacking significant Muslims, due to the events of Partition... but Brazil has a good proportion, surprisingly), but the best that can be said is there might have been fewer internal wars for this "ethnic" mini-League Of Nations (apart from Iran-Iraq, Iraq-Kuwait, whoever-vs-Yemen, Sudan-vs-Sudan, the whole multi-way Syria thing, the continuing post-Gaddafi Libya split, etc).
The best that can be said about any particular lumping-together of 'Arabs' is that it makes their interactions with 'non-Arab nations' more defined. Not that I'm saying that there's particularly more turmoil in the Arabic world, witness what "Europeans" have internally disagreed with each other about over even just the last century or so, and even back when they had a shared Lingua Franca (whether Latin or, in certain circumstances possibly due to the not-actually-that-short guy with the hat, French), at least at government/diplomatic levels, and when nominally "the Vicar Of Rome" had the most wide-spread power over even most Kings/etc.
The ethnic differences across 'Russia' (ex-USSR, or 'just' Russian Empire) was always inevitable by the sheer breadth of territory hoovered up (from pre-Revolution to post-WW2), encompassing various peoples who might otherwise have had steppes and mountains and deserts and possibly even seas between them in their histories (especially at the time when Russia nominally held Alaska, and its natives along with Russian incomers). Not piddling things like whether you were Polish or Austrian or (East) German at heart but found yourself moved across one or more borders despite never having physically shifted. China is a similar 'pocket mash-up' (but with greater density), striving more for the national-fiction that "there are only Chinese" across the 'Kingdom, Old and New'. If "The Arab World" seems more homogenous, it's only because it's been more designed to apparent ethnic homogeneity (the British Empire went the other way and just did not care about that at all), but still leaves many cultural differences (the B.E. at least supercicially tried to get 'members of the Empire' to consider themselves Culturally British (if not English!), even if the Brits(/English) back home might have (and various descendents still) thought otherwise).
All I actually know is that one cannot broad-stroke social identity without compromises. If I've apparently labeled or mislabeled any actually individuals, in any of the above, it's totally unintentional to have tied you down at all, whether you think I was right or wrong, and I've just thrown out loads of wide-ranging options to cover pretty much any continent except Antarctica (not even by design, but I... oh wait, I didn't mention anything covering Aus/NZ, either... and now I realise that but it would be gilding the lilly to (e.g.) go back up and insert anything about the Aboriginal and Torres Strait Islander 'meta-nation', or hedge the other side by grouping the Polynesian peoples and lands).
Maybe "Arab" is a useful term, if qualified. But it's also an easy pejorative that can be (often wrongly) applied to non-Jewish Semitic but also far afield. Not as bad as "Asian", which tends to mean anything perhaps east of Arabia (but can stretch into the Middle East, or "African Asian" diaspora) that isn't actually Oriental (and "East-Asian"), in British terms (inclusive of India, wherher that's considered geologically right or wrong), but has a different footprint from a US perspective (as I understand it), and for most of us wouldn't include Siberians/similar (hi Max The Fox, if you're reading this, are you on the Asian side of the Eurasian divide, or am I misremembering what little I know of you?) who geologically are firmly Asian. But in anglophonic (and certainly British colloquial terms), there are of course more insulting terms ("Sand <N-Word>s", etc) yet it has a(n inter)national-stereotype potential that can be innocent and accurrate in the mouth of one speaker but nasty and slanderous in the mouth of another. In the context of "all Arabs are..."-type speech, it's probably not going to be taken/intended as the former.