When I hear people talking about how a plan is "serious" about the US budget, when I hear talk of "necessary" pain, I know that that the pain is unnecessary and the plan is junk. A person who has made bad mistakes, and who needs to do hard things in their life to set them as right as possible, may talk like this. But that's not where this is at. This about making the elderly and poor suffer, and further impoverishing the majority of the USA.
And that is what it takes to be "serious" in the politics of these times: making your "inferiors" suffer. Because, if the Serious People couldn't do this, they might have to undertake some austerity in their own lives.