I’m not sure why people like you feel so confident that some small segment of vocal lefties lost the democrats the election. They are such a small percentage of the actually voting population and strategic voting is just not how most people vote.
The reality is many democratic voters were simply not motivated to vote for an administration that was more interested in supporting a genocide than dealing with the riding cost of living. You can argue that’s stupid or irrational but that won’t affect how voters actually vote. You might as well be yelling at a brick wall. It won’t change anything.
The fact is that Biden, Kamala, and other high level members of the Democratic Party knew that supporting a genocide might cost them the election. They did it anyways. They cared more about Israel’s ability to bomb children than they cared about protecting the American people from a second Trump term. The blame lies entirely with them.