"From the river to the sea" does not mean killing all the Jewish people in the region. It is not a call for genocide. Palestinians have repeatedly asked people to stop saying that and stop perpetrating antisemitic violence under the guise of solidarity.
https://jewishcurrents.org/what-does-from-the-river-to-the-sea-really-mean
Conflating that saying with a call for genocide, either intentionally or otherwise, misconstrues the movement and what Palestinian liberation looks like in the eyes of Palestinians. It also stirs the pot of islamophobia and orientalism by painting the brown Muslims as violent and genocidal by default, and it fuels Christian Zionists who really just wanna warmonger Israel into the rapture... which is actually antisemitic and genocidal.