Unfortunately the Democrats need slightly more than a bare majority because some Democrats might as well be Republicans.
Kamala has also stated her support for exempting this legislation from the filibuster, something Biden didn’t do. She wouldn’t technically have the power herself, but might get Senate Democrats on board.
Despite the obvious common root in “populism” and “popular”, I don’t think that’s a fair “nutshell” description of populism at all.
The central core of populism is opposition to an elite ruling class. Right wing populism tends to attack education and expertise which does fit loosely with your description, but left wing populism is more focused on wealthy elites. Wealth has always been a terrible proxy for merit or the ability to rule.
To be against populism you either have to disagree that we are largely ruled by a class of elites, or think that being ruled by elites is not a bad thing. Anyone that thinks elites are not in control of the economy and political system in the US is borderline delusional. Anyone who thinks the elites got there by merit need to learn a lot more about figures like Elon Musk, Trump, or the Clintons.