Kamala Harris is interesting because she's a machine politician. There aren't a lot of those left because there aren't a lot of real machines left in America, but San Francisco has one and she's part of it. The political skills that have gotten her to this position aren't really electoral but instead involve forming connections, which she has in spades in San Francisco and in Sacramento.
The last time there was a vice president like this, he was only in that position for a matter of months before Franklin D. Roosevelt died and he became president. We're in sort of uncharted territory with a vice president like her, and right now she's in a job with no clear responsibilities, cut off from her source of strength in California and mostly cut off even from Congress.
The media framing of her in the last two years suggests two things, both of which can be true:
- Kamala Harris has not endeared herself to people she has needed to make strong connections with and she has consequently struggled to have any sort of role in the current administration.
- People in positions to talk to reporters see Kamala Harris as a potential rival and so they're informing against her to the press.
That Gavin Newsom is very openly looking to run for president suggests that Harris really has missed an opportunity, because they can't realistically both run serious campaigns and Newsom wouldn't be so bold if he thought that she had a real shot. If she does just go back to California when her time as vice president is through, that would be very normal for vice presidents.