This is so disingenuous it hurts. The criticism is that she intends to have a huge fight to pass the public option right away, somehow win it, THEN have ANOTHER, EVEN HUGER fight three years later, and somehow also come ahead in that fight, all while passing all the other stuff she wants to pass.
It's pure wonk fan fiction, and it signals that she has basically settled on the Mayor Pete solution but still wants to rhetorically signal to the Left that she "wants" single-payer. I don't mind her and would happily vote for her over Trump, but come on, her whole M4A rollout has reeked of bullshit.