Interestingly, the mechanics of this seem backward. A major problem with the Fed's operations is that operations on financial markets take 12-18 months to spread to the real economy, so they have to target interest rates
now based on what they think the economy is going to look like in 12-18 months. Conversely, money going into or out of the average person's checking account
now affects what they do in the real economy
now, without a lag time. When we've recovered from significant economic crises (2008 and 2020), it's often been through direct fiscal stimulus.
It seems that the logical thing to do would be to put money into the economy through directly giving it to citizens, and then take money out of the economy through interest rates, by making it more expensive to borrow and reducing business investment. Typically you want to put money into the economy in a hurry, in response to a crisis, but you want to take it out gradually, so that businesses can plan ahead. MMT's framing of this still seems backwards, even if they've realized that fiscal and monetary policy are two sides of the same coin. You'd also get a lot less political resistance to the fiscal policy side if it involved giving people money rather taking money away from them.