Again, the question raised by @greysea’s assumption was whether “actionable things that Administrations are capable of doing on their own would largely be the same whether Biden or Bernie.”
If you think @greysea is right that, in the face of a Republican Senate, their actions would “largely be the same,” then aren’t you saying it does not matter whether Biden or Sanders is elected?
(Obviously one can say that while also preferring one nominee over the other for reasons of “electability.”)