One very common form of zionist propaganda is the denial of Palestinian nationhood. The idea is essentially that Palestinians do not constitute a unique or independent national community, that they are in fact undifferentiated Arabs, and thus possess no unique right to self-determination and can simply be dispersed into neighbouring Arab-majority states.
Even if this were true, it would obviously not justify the mass displacement and subjugation forced upon Palestinians by the state of Israel. But there is a more fundamental level on which this narrative falls flat.
If we consider the trans-Atlantic slave trade, it is clear that the many millions of Africans forced into bondage and transported to the Americas did not share a common national identity. These were people of very diverse ethnic, linguistic, cultural, and religious backgrounds. And yet we see all over the history of the new world the demands made by Black people for the liberation of Black people. People were very clearly aware of on what grounds they were being oppressed and formed communal bonds accordingly.
The point I'm making here is that Black identity in the Americas does not predate the oppression of Black people but instead arises along with and because of it. The point is that regardless of the history of Palestinian nationalism before 1948 (which you probably should not learn from the people diametrically opposed to Palestinian nationalism) the common experience of displacement, oppression, and occupation at the hands of the state of Israel since then has provided the foundation for increased Palestinian self-identification and the Palestinian national liberation struggle.
You cannot oppress a people out of the knowledge of their own oppression. Much as the intensification of white supremacy in South Africa fueled the growth of the anti-apartheid struggle, the intensification of zionist violence strengthens the resolve of the resistance to it. Bezalel Smotrich can say all he wants that Palestinians do not exist, but a child orphaned by an Israeli airstrike in Gaza knows that they are an orphan because they are Palestinian. This is why zionism cannot win a permanent or total victory. It creates its own antithesis.