It probably cost some votes, but those polls didn’t have the actual reasons people didn’t vote for Harris. That is: she is a woman and she isn’t white. It’s the hard truth but no poll is going to include “are you racist?” or “are you sexist?”
Also, anyone with even part of a brain knew that trump is going to make things a lot worse in Gaza than Harris.
You answered your own argument with that link. How many female, Muslim heads of state are from the United States on that list? If you honestly think that 6 million Americans stayed home over Gaza you don’t have your finger on the pulse of America. Again, I’m sure votes were lost due to Gaza, but it isn’t the main reason why she lost.