Just because you don't follow her doesn't mean she's not pushing progressive things in off years. She was the first Senator to call Gaza a genocide, voted in the progressive block on all the votes I can remember where there was a progressive vs. moderate split, and is constantly advocating for more progressive positions on things. Which is all any of the progressives do because their actual power as legislators is basically nil and all they have is their voice.
This just seems to be a kind of nonsensical made up version of her. You're both criticizing her for (supposedly) toeing the party line while also complaining that she sowed division against Harris through the general election (something that's just entirely made up) and led Warren voters to stay home (which is just wildly out of step with their whole vibe). Is your imaginary version supposed to be a "controlled" party loyalist or a rabble-rouser sabotaging the party nominee?