I agree with you Raskolnikov.
Also governments tend to run deficits, they spend more than they raise in taxes. This money is then burrowed from the bond market, not printed. Mr Shigemitsu gives a good story which could describe how money works, but we don’t run that exact system.
Here is a critique of MMT I have seen which I tend to agree with.
https://blog.usejournal.com/whats-wrong-with-mmt-a41e10c7203b