I actually think there was a lot more interference in 2016 on Hillary's behalf. I also think a lot of Democrats put their preferred candidate aside and went for Biden during the primaries because he had the best chance of beating Trump. Beating Trump became the number one priority.
Looking back, I also don't think any other candidate could have beaten Trump. Of course there's no way to prove that as it didn't happen. Biden was simply more acceptable to that large group of non-affiliates known as independents. No national candidate these days can win without them. It was the independent vote that defeated Hillary, it was the independent vote that defeated Trump.
We have moved into an era where both major parties need to ascertain who can win and place that above ideology at times or lose the election.The independent vote who gave Biden his wins in Arizona, Georgia, Wisconsin, Michigan and Pennsylvania and it was the independent vote in 2016 which gave those states to Trump.
It's high past time that we start electing Americans to congress and the presidency who put America first instead of their political party. For way too long we have been electing Republicans and Democrats who happen to be Americans instead of Americans who happen to be Republicans and Democrats.