They kept the good stuff under wraps and tried to play it safe but not spooking anyone with “communism.”

This is it exactly, and I feel like this bit of this Salon article (arc’d) perfectly captures why this happened

Tobias described a dynamic where campaign staff and candidates are hesitant to publicly push back on the assertions of billionaire donors like Hoffman, even if the campaign doesn’t intend to let them direct policy.

Tobias indicated that the apparent influence of the super-wealthy has a dual effect. It undermines the Democratic Party’s support from its traditional base by steering policy discussions away from economically populist ideas that go against the interest of the wealthy, while simultaneously helping support candidates who are charismatic but don’t come into politics with a consistent ideological framework.

The influence of billionaires was directly early in Harris’ bid for the presidency when moguls like Mark Cuban warned the Harris campaign that a billionaire tax, for example, would be too aggressive, according to the Washington Post. Other business executives, like Tony West, the chief legal officer at Uber and Harris’ brother-in-law, also served as advisors and, according to the Atlantic, helped steer the campaign away from criticism of corporate power.