There's an old axiom that timing is everything in politics. I think the result of the Democratic primary is one of those timing issues.
The overbearing political force in this timing was the Trump base. Despite three years of mismanagement, lies, and ad hominen attacks, the base has been solid behind Mr. Trump. I'm not exactly sure why, but it is what it is. If the goal was to beat Mr. Trump, the centralist candidate of Mr. Biden was a better political move. Mr Biden can find votes in the center that the more progressive candidates might lose.
When I saw Mr. Trump holding a Bible in front of the church, I thought that photo-op is going to be a political turning point*. I believe that Mr. Trump cannot win the election. And all those generals taking a stand came shortly after.
But the Democratic primary was effectively over. In these times, any of the six top runners in the D primary could probably beat Mr. Trump. But, like it or not, Mr Biden is designated the leader. Had Mr. Floyd met his untimely death six months ago, there very well may be a different D at the helm. Timing!
*Politics is indeed unpredictable strange. I will just say that November is now 90% in D hands. Only they can screw it up. BTW, I predicted a coin flip for 2016 long before election day--and the pundits could only see a clear Clinton win.
I doubt it very much your article(s) are going to change the Democratic Party in any way. I think you would have better luck trying to convince a lion to stop hunting gazelles and become a vegetarian.
But it time for USA to move beyond its political parties. May I suggest you take a look at
Tiered Democratic Governance
No more Democrats. No more Republicans. Mr. Trump would stay out of politics. People like Mr. Sanders, Ms. Warren, and Mr. Yang would find natural places in this TDG befitting to their capacity for public service.
Put your energy towards rebuilding American democracy.