I think the angriest will just stay home, vote third party or leave the presidential ballot blank. Ultimately, though, most will still vote Biden because they know Trump will be worse for Gaza and Muslim Americans.
I think the discontent runs deeper than you give it credit for. There’s still time for things to change, though.
I think there are many groups using Israeli/Gaza as a reason to express deeper anger towards Biden.
1. I made a thread about this a while back but many Arab Americans were already going to flip to Trump or at least not vote for Biden pre-10/7 due to some of their more socially conservative religious views. This can be shown in the 2022 midterm results where places like Dearborn and Hamtramack in MI were the only parts of the state to swing hard right from 2020 Pres --> 2022 Gov and this was pre 10/7.
2. Many progressives who were never going to vote for Biden - many of whom perhaps didn't vote for him in 2020 or Clinton in 2016. These types are angry and want to burn the system down which they don't see Biden as the right person for. There are so many cases I've seen online where a progressive twitter or Instagram account says "I'm so fed up and won't be voting for Biden" - then people go back through their history and finds they were never a Dem voter in the first place.
3. This sort of ties into the last group but young people with a lot of economic anxiety. Many of the biggest economic problems right now (i.e. high housing prices) disproportionately affect young people while things that are doing well (i.e. the stock market) tend to not matter as much to younger folks. I think many of these types use Israeli-Gaza as a vehicle to express their anger when the root of it is more based around the economy.