The definitions aren't muddled. Apartheid [1] and genocide [2] are both defined by the UN. Apartheid in particular is also objectively true. Do Israeli Arabs have the same rights as Jewish Israelis? No, objectively [3][4].
As for Palestine being its own country, it clearly isn't. Palestinians live on land claimed by Israel and recognized by pretty much every country in the world. But what if it was? Then Israel is illegally occupying it. Is that better? Why does this matter? Does one make the treatment of Gazans (in particular) more acceptable?
> Even worse, for most Israelis (who are 70% of Arab descent), the country of Israel no longer existing could mean a real genocide for the Israel side!
You can't use a theoretical future genocide to justify a current actual genocide. Also, it's ahistorical. Did this happen when apartheid South Africa ended? What about slavery? No, what actually happened was the former oppressors continued to commit violence against the previously oppressed.
[1]: https://legal.un.org/avl/ha/cspca/cspca.html
[2]: https://www.ohchr.org/en/instruments-mechanisms/instruments/...
[3]: https://decolonizepalestine.com/myth/all-israelis-are-equal/
[4]: https://www.amnesty.org/en/latest/campaigns/2022/02/israels-...