The name of the function, what goes in and what goes out in most cases should be enough to get a good idea on what the function does.
It also helps to make a diagram of how everything ties together. Just boxes and arrows is enough.
When writing your own code, it takes a bit of experience to know when to put something in its own function. It's very obvious when you're replicating code. It's also very common to cut things up when a function gets too big. Look for bits of functionality that you can give a good name.
I think the basic reasoning is some form of:
"If you support Palestina, you are against Israel. And you can't be against Israel, because then you are an anti-semite and that means you support Hitler."
It's mainly prevelant in western countries that historically support Israel. I do think a big part of that is some historical shame/feeling the Jewish people are owed something, given the genocide they had to endure in WW2. And of course a touch of geopolitics. And right wing politicians using Israel as a way to position themselves (I guess they hate Muslims more than Jews?).