You're blaming people for being strongly anti-genocide. That's basically absurd at face value. If you wanna argue against being a single issue voter, that's a conversation to have. However, "I oppose genocide." is kinda the single best single issue to rely on, if someone is inclined to be one.
All the while, Harris knows the risks. Don't blame voters for Harris's conscious choice. If you alienate your base, you deserve to lose your base. Deal with it... I think she still has the votes, but that is the risk for every candidate, and it always will be.
Phone calls are a trap. Little good comes from answering them.