The population of Gaza is actually the concentration of the descendants the former non Jewish population of nearby communities in Israel who were driven out during the Nabka. Many in Israel are calling this war Nakba 2.

Here is some quote from Israelis in this regards: https://thehill.com/opinion/international/4313276-israel-is-...

There are also policy papers to this effect that leaked from Israel: https://www.cbc.ca/news/world/israel-gaza-palestinians-conce...

So this fear is an outcome some are advocating for but all world leaders are strongly opposed.