She gambled that moderating her position on healthcare would pick her up a lot of centrists without sacrificing progressive support. Wrong on both counts, and that bizarre takedown she attempted to do of Bernie didn't help. Also, trusting Joe Rospars, the worst campaign strategist in American history, was a bad idea. He replaced her policy-driven focus with "Big Structural Bailey." Ultimately she spent a lot of her career fighting Credit Card Joe on various consumer issues and she's the reason he sailed through to the nomination.
LOL no, that is definitely not true. Are you seriously still propagating this myth? Warren dropping out would not have saved Bernie. Even if he took all her votes AND Bloomberg didn't drop out, Biden still would have dominated Super Tuesday. If Bloomberg (who got more votes than Warren) had dropped out too, Biden would have just dominated even harder.
Biden did not win because of Warren; Bernie was always doomed in a contest that came down to him and almost any other single candidate, simply because he was a factional candidate who banked his entire strategy on being able to win a plurality of ~30% of voters, never seeming to take into account the possibility that Democrats would learn from the 2016 GOP primaries and consolidate around one candidate against him.
If anything, a two-way Biden vs. Warren contest probably would have been closer. She would have kept most of the progressive support and gotten more moderate/establishment support than Bernie ever could have.
Plus, in what way did Warren moderate her position on healthcare? She also supported Medicare for All, she just offered more details on how she actually wanted to do it than Bernie. Is providing details and plans rather than just shouting your demands considered "selling out" to socialists or something?