If democrats were honestly concerned for the health of the democracy, they’d be paying more attention and addressing the concerns of those people threatening to vote 3rd party, abstain, or vote for a fascist.
I think they honestly are concerned for the health of the democracy, but I think they’re limited in what they can do to address root causes because of their funding apparatus. Biden specifically strikes me as a person that cares deeply about the well-being of the citizens of this country and if he were able to wave a magic wand and reverse Citizen’s United I think he likely would do so, but it unfortunately is not that simple.
Some Democrats are fighting in an asymmetric war as well (e.g. AOC and other “justice dems”) which makes them less effective than they could be and in a constant electoral squabble, but keeps them from completely compromising their principles.
Ultimately, there is no issue as continually relevant in modern US politics as the power of money in politics (a.k.a. regulatory capture) and I do not share Biden’s optimistic outlook for the future of this country given its current political state.