To quote Jim Rickards: "economics is a science but most economists aren't scientists."
DSGE is bunk, so is the Phillips curve, so is the EMH (more finance than economics), so is a whole bunch of stuff. I subscribe to complexity economics, not the standard model. But MMT is even worse than the mainstream stuff. Even central bankers think it makes no sense (https://publications.banque-france.fr/en/meaning-mmt).
You do know mainstream economics isn't science right? Because it's completely unable to prove anything it predicts