That $3.2 billion would be enough to pay for 23,000 Americans' college education. Is that more valuable than giving weapons to Israel? Of course it is. Even a single college education is a better use of the money.
The rhetorical tactic of citing some much larger number to justify a misuse of funds is meant to obfuscate and confuse, and it's not a good faith argument. It's like a mayor saying "yes, this program is wasteful and corrupt, but look at how big our military spending is! Why aren't you talking about that?!". Or "Yes, I may have created a made up job for my brother, but look at the trillions we spent in Afghanistan! Why aren't you talking about that?!"
We should not be falling for that type of rhetoric when calling out government waste and abuse.
There is no reason that the U.S. should be sending any aid to Israel (or, for that matter, Egypt), it's not a poor country, there are many more countries deserving of the aid, and the aid is being used to increase the militarization of a region that has already had too much military conflict.