See, I barely even know how to parse most of those claims.
I'm not sure I know what a "40 year debt bubble" means.
I don't see the necessary link between "supply-side expansion" and "massive household debt."
"America is in the forefront of world economies and we are much better served by demand side policies." is a non-sequitur. A nation on the technological frontier needs to be consistently pushing that frontier, and I don't see the link between R&D and "demand side policies" except in a heuristic, ill-defined, "expectations of future demand drive current R&D spending" sense.
I'm hard on you because I know there are neurons firing in that brain of yours.
These claims, though, are slightly more sensible.
One very basic problem is that the Fed is paying interest on reserves, so it doesn't really matter where the money is injected - it will end up at a bank, which will then deposit it at the Fed.
I have less faith in fiscal policy than you, but reasonable people can and do disagree on that point.
We aren't exactly discussing the same things. I won't address most of this because that would take more attention than I'm emotionally invested in.
But supply side policy/
régulation and
asset bubbles are very closely linked, and I would say that supply side policies create asset bubbles when there's a lack of demand for there to be sufficient markets for increased investments. This necessarily leads to riskier investing (and trading), especially as profits are driven down as everything gets arbitraged to "equilibrium".
But it also increases "supplies demand for demand" (as all this extra money needs somewhere good to go), which could be solved by reliable things like wage growth accompanied by more leisure time. But that does of course limit the agency of capital as it loses dominance. So instead brilliant entrepreneurs and "intrapreneurs" create new markets to create untapped demand. This untapped new demand has mostly come in the form of household debt. (Some others have been funded via advertising (where the customer is the product)). This is a historical correlation or causation, not one that, as far as I can see, is some sort of economic axiom.
When consumers are at their limit, but there's tons of capital sitting around, that capital will find its way into speculative bets that household debt financed demand will grow and create new markets, or it will invest in profitable ventures that will simply knock off old ventures, an often zero-sum economic game with transaction costs if the new product or technology doesn't change the structure of the economy.
That's just mad broken.
It's perversely somewhat analogous to a Keynsenian description of full employment: there's no more investment. Except it's not full employment, it's full debt tapping. And it's not no investment, its investment into a false liquidity preference that is solidified, so to speak, by speculating that there will be new sources of debt.
Fiscal policy, like monetary policy, is ultimately the creation and destruction of money. Both have their advantages. It's just a lot more convenient to change a number in an excel document to stimulate the economy than to have a bureaucracy hire people.
Perhaps this demand shortage I keep hearing about is because everyone is up to their eyeballs in debt and can't possibly consume more?
I'd be satisfied if most people in this thread felt at least a little uneasy printing $1 trillion per year, but I get the feeling the opposite is the case. (ie want more printing

)
The world consumes and creates more energy, the world needs more dollars to represent it.
But yes, that is the demand shortage in a way. We have had no meaningful wage growth, but have had massive increases in aggregate demand due to household debt. Credit cards, sure, but mortgages and refinancing of homes during a decades-long housing bubble basically made households behave as though wages were going up. Pop goes the bubble, and the easy access to credit, and pop goes the demand.
Fix the demand shortage? Increase wages. Increase pensions. Increase welfare. Fund projects. Increase public service. You do this until you reach full employment, which probably takes more employment than our theoretical level of full employment (during WW2 we saw it go down to what, 2%?)
Household debt and government debt is not the same. It's a shame we even use the same word.
Heaven help us
I think the reason people get upset by this concept is because of the emotional charge of the terminology. Another way we could put this is "The government keeps commerce alive by making sure that the physical energy used to create our economy and material living doesn't dry up in a liquid-free deflation death trap as the dollars stop flowing". The only reason to run a surplus is when the economy is doing so well that you are literally trying to destroy parts of the private sector. Kind of like raising interest rates.
Now that's some radical stuff right there.