Of course Harris had a plan. And we all know about trump's "concepts of a plan."
What I'm saying is when out campaigning, especially in critical swing states that decided the election's outcome, she couldn't dynamically reapportion or pivot her messaging focusing on the major concerns of her audience, which were largely economic based... trying to get ahead in life, putting food on the table, putting kids in college, buying a home, etc. And instead putting valuable time on trump being an awful person. Which apparently people didn't care too much about.
She did well in other states with people in better shape economically and having different concerns (trump being awful/wanting to be a dictator/dangerous/a liar/a conman, etc), as attested by the large number of votes she won.
I don't think Newsom will be making that mistake in 2028.