"and everyone who supports it boils down to the theory that if governments can just tax enough to hold off inflation they can spend as much as they want" It do

"and everyone who supports it boils down to the theory that if governments can just tax enough to hold off inflation they can spend as much as they want" It doesn't boil down to that. That's looking at it from the wrong angle. The line is that to spend there has to be something to buy. If it is available to buy and nobody else wants it, then why not bring that item into use (largely the unemployed). Spending stops automatically when you run out of things to buy priced in your currency at a price worth paying. If you see somebody talking about raising tax rates and lowering tax rates in relation to MMT on a counter stabilisation basis, then that person either doesn't understand MMT, or you've misunderstood what they are saying. The primary stabilisation mechanism of MMT is the Job Guarantee and the secondary one is government demanding a lower price for goods and services it purchases, which it can force on people because otherwise the system will run short of spending. Taxes are a very distant third or fourth in the control stakes. In MMT they are essentially a garbage collector. There to ensure we don't overcommit the system.