Netanyahu is most definitely no angel and he's in large part responsible for the current situation including Oct 7 by propping up Hamas for his own political gain. However, what it happening in Gaza is not ethnic cleansing. Ethnic cleansing is systematic killing of civilians based on ethnicity. This has happened multiple times in history, but it's not what's happening here. There are way too many innocent casualties, yes, but nobody is systematically killing Palestinians. I don't know what this "relocation" plan is; forced relocation is of course bad, but it's much better than systematic killing (which is what ethnic cleansing is), and it's also arguably much better than civilians being stuck in a war zone.
Truth of the matter is that it's very challenging to fight an army of 40k terrorists who are intentionally mixed with civilians in order to maximize civilian casualties. How would you deal with a terrorist organization like that? I don't think anybody has a good answer.