Those who are suggesting Biden do this or that, are forgetting the most important thing about coup d'état: his “followers” would need to actually act on his orders.
And even if they were to do that, which I doubt they would, I don’t think SCOTUS made the rank and file immune to prosecution. While they may have made it harder for Jan 6 obstructionists to be pursued, I’m pretty sure that’s limited to those Jan 6’ers. So anyone following Biden’s orders would likely see jail (or worse). Sure Biden could pardon them, but that would only happen if a) Biden was still president after a failed coup, and 2) the people being pardoned would need to be prosecuted first, which is lengthy, disruptive, and expensive.
This only helps republicans, because as horrible as they are, the one thing they excel at more than their capacity for hate is their ability to unify and work together. Democrats… yeah, ain’t happening.