The problem is that Bernie is too left leaning for the right of the Dems. Its highly likely people who supported and funded Hillary would have withdrawn their support and money, and some may have even given it to Trump instead. You can see with Mamdani how that's playing out, they'd rather field Cuomo as a spoiler candidate than let a progressive win.
Dont get me wrong, it was clearly manipulated to steal the nomination from Bernie, and Bernie would have been the better candidate and president than Hillary, but I no longer think it would have been the slam dunk that I did at the time he would get in, simply because hes against both sets of interests at the top of the Dems and the Repubs.