No, not immediately, and also for very different reasons. Palestinians, no matter where they end up, have a large sense of identity and continue to identify at Palestinians, be they Muslims or Christians - continuing to speak in their own dialect for example - while Israel expends enormous resources convincing themselves and anyone who will listen that "there is no such thing as a Palestinian". Palestinians by and large do not want to leave Palestine, because if they do they would likely never be able to return - especially if forced out by the IDF.

• Lebanon has already absorbed Palestinians but Lebanon has a small population that is in a delicate demographic balance between their various religious groups - Maronite (Catholics), various Orthodox Christian, Sunni, and Shi'a, among many others. Lebanon is a creation of France in order to have one country in the Middle East be majority Catholic, but the demographics have shifted (due to emigration, birth rate differences and incoming refugees) and led to various civil conflicts, including a devastating civil war which drew in all their neighbors, and the current power sharing agreement is a precarious peace while larger foreign powers still meddle there, supporting one group or another. Hisbulla for example is a Shi'a Iranian proxy with a fairly large and kind of effective military wing independent of the state, while the West funds the official yet ineffective and probably incredibly corrupt state military. Adding more people, a majority Sunni, upsets the balance further, so Lebanon is reluctant to do so, understandably.

• Egypt has also absorbed Palestinians over the years, but Egypt is also very careful about accepting people whose politics are principally driven by religion, especially Sunni Islam. Not saying that all of Gaza is politically religious, but many are, and Hamas definitely is. Allowing Israel to easily annex Gaza by allowing Israel to expel all Palestinians there to Egypt would cause the Egyptian State all manner of trouble. Also the pro Palestinian cause is very well favored by ordinary Egyptians, so the government cannot simply help Israel to kick them out by absorbing them. Either way you see it, it is not in Egypt's interests to accept.

• Jordan has absorbed more Palestinians than anyone else. 60% of Jordanians are Palestinian in origin, and there are hundreds of thousands of refugees there also (i.e Palestinians without Jordanian citizenship) living there. The source of conflict between the PLO (whose leadership was exiled in Jordan at the time) and the Jordanian monarchy at the time was not sparked by the Palestinians "just being there" but rather that the Jordanian King Abdulla was opposed to Palestinian nationalism, and vehemently opposed the idea of a Palestinian state, since he always believed that any land that did not become Israel was his to rule by right, since Britain offered his ancestor all of Palestine during WW1 (all while double crossing the Arabs to offer it to the Zionist movement also). The Jordanian monarchy is not native to Jordan but rather originate in Arabia. Anyway this put the monarchy at odds with the goals of the PLO and Jordan failed to rein them in. Jordan is very receptive to Palestinian refugees though even though they are demographically overwhelmed by them, and lack the resources to absorb so many (Jordan is one of the driest countries on the planet).

• Syria is in no state to absorb millions of Palestinians, although before the war they had done so.

• Saudi and Gulf states don't really give much of a shit. They are happy to accept Palestinian workers, often educated professionals such as teachers, doctors, engineers and such. Not millions of refugees.

Essentially, each country has reasons to not do what Israel wants. And two of the major reasons on top of it all is that it is what Israel wants, and it is not what the Palestinians want. Palestinians want their homeland.