You're right about Bernie, Mike. But you're wrong about Biden. The man is not fit to deal with the responsibilities and stresses of the Presidency. Anyone who thinks so is not accepting reality.
To give you an analogy: Say you're an NBA basketball coach and your best player is getting old and not what he used to be. He's causing you to lose games and you have better players on the bench. Do you stick with the old guy or perhaps it's time for him to retire. I think any sane coach would put him on the bench and the ownership would suggest his retirement. Everyone eventually becomes "Over the hill."