I kbow this is TLR and I have to dumb shyt down but let me make things simple for your simple thoughts.
Trump was gonna claim Bernie and Warren are socialist and woukd turn the countey into Cuba. Even now they are still pushing Biden is a socialist. Trump wanted to face Bernie. His only hope now is to make Biden look incompetent which is what his whole base is pushing now.
So what, how is SoCiaLiSm is looking now?
By that rationale Trump is unbeatable
Trump isn't unbeatable. He only won because he was facing HiIlary (same person who lost primary to a newbie Senator and had to cheat to beat a Democratic Socialist).
Having said that the electoral college means it's tougher for a Dem to win than Republican.
Certain states are already marked blue or red.
Bernie's strengths are appealing to those purple states that could go either way. (assuming he ran a more competent campaign in the general)
Looking at Biden, he's a weaker Dem candidate than Senator Kerry was - the only way he wins if Trump hands it to him by going full Trump.