At some point, particularly given the last 40 years of evidence to the contrary, people need to simply accept that monetary expansion does not "cause" inflation [1]. Inflation is not a monetary phenomenon at all. Inflation is a price level [2] phenomenon largely driven by trade imbalances. Inflation is about market power, or what some call pricing power. The common case here, btw, is when your external partners from whom you need to import critical goods get even a little bit pricing power then you will get inflation. China is seeking to own all its externals and deliberately suppress any such pricing power not driven by its own banks.
[1] https://www.bloomberg.com/news/articles/2018-03-22/the-great...
From where I sit, the past 40 year have shown that, if you grow the money supply only a little bit faster than the real economy grows, then you only get a little bit of inflation.
Inflation must be kept in check or bad things happen.
Maybe the current levels are sustainable. But not all increases in deficit are sustainable.