I didn't read the article, but the excerpt you posted seemed pretty reasonable? Saying "independents might not vote for Bernie Sanders" isn't such a far out opinion you know. It's probably much easier to convince them to vote for a moderate in that regard. Biden was probably still the best moderate candidate up there, but thanks to all the media hype around the 4 or so candidates vying for the non-Sanders/Warren base, it's split Biden's votes and helped Bernie a lot. Nevada is honestly the 1st really good result Bernie had. Iowa and NH were decent, but what was surprising is that fewer people voted for Bernie in 2020 in NH than in 2016.
So ignoring the independents again.... You better hope that democratic turnout is big, b/c democrats can be pretty bad at turnout at times.
I will say this thread is a pretty ridiculous echo chamber....