You could get rid of both Biden and Trump, whoever replaced them would be beholden to the same imperial corporate interests and be just as vile with their policies.
You could do Putin or Zelenskyy in, and another capitalist oligarch would just take their places.
If Netanyahu disappeared tomorrow, Israel has plenty of genocidal politicians ready to fill his boots.
The real world isn't a Marvel movie, there is no single "ultimate bad guy" to rally against. The entire systems of these places need to be overcome.
Yes, that is why Biden going out of his way for Netanyahu is so insane.
Biden could send Netanyahu to the ICC, offload all the bad decisions on him. Then replace Netanyahu with whoever is next in line and continue the genocide without pausing for even a second.
I think perhaps one of the unspoken goals here is that Israel be beyond reproach; he doesn't necessarily care about Netanyahu, but instead cares that Israel be absolutely beyond the criticisms that are traditionally only levied against non-Western countries.
Also if the Israeli government was condemned wholly or in general for genocide, it would put them in the public consciousness in the same area as all the countries we're taught to hate and to shrug when violent war comes to their shores.
He can still point to Bibi for now and have that straw man. Even though Bibi wants a republican, it's so foolish however it's sliced.