It just isn’t as good of a political strategy to go after progressives, who the DNC knows overwhelmingly vote dem regardless. The number of leftists who won’t vote for the democrats just isn’t high enough for them to care, which unfortunately means they pivot towards moderates, independents, and moderate republicans in basically every election
I’m not saying this is what’s definitely going to happen, I’m saying there’s a chance democrats lessen their support for Israel after the election since they won’t have to care about the (depressingly large) influence of pro Israel groups in our elections.