There are biases on all sides, and it’s often hard to extricate oneself from them to see the facts as they are.

You could flip the question and ask why is so much of the world anti-Israel, no matter what?

The data on this is that in 2020 the UN adopted 17 resolutions condemning Israel and 6 for the rest of the world.

Now it’s possible that Israel is so much worse than the rest of the world, and the US is biased. Or perhaps there’s a lot of anti-Israel bias globally and the USA is actually closer to neutral.