Recommend you take a look at this to see more factors involved in inflation, in a more quantitative light: https://www.lynalden.com/inflation/.

The reason CPI is a terrible metric is because measuring inflation is very difficult and somewhat arbitrary (see for example: hedonic adjustments). M2 is a significant, consistent, and logical factor. Even from 1980-1986, rapid changes in M2 consistently correspond to a change in inflation. But there are other factors, like real economic growth, population growth, changes in size of the labor force and velocity of money.

Look I am aware of a host of factors that in theory influence inflation and the multiple different ways it’s measured. I am also perfectly willing to acknowledge there is a connection between M2 and inflation. But, when historical correlations are this weak you can’t suggest A predicts B when it simply hasn’t.

Not everyone has an eye for data, but this is a pretty clear correlation (time delayed, of course) as far as real world macroeconomic signals go. Contrary to your claim, significant increases in M2 have historically predicted increases in inflation with high probability for over 50 years, even without controlling for other factors. And all the people predicting decade-high inflation and asset inflation since last year have been right so far.

> as far as real world macroeconomic signals go

That’s some serious weasel wording right there. Either a model fits real world data or it doesn’t, ignoring all those times a model failed isn’t an eye for data it’s a delusion.

> And all the people predicting decade-high inflation and asset inflation since last year have been right so far.

That’s little different from walking into a room full of broken clocks picking those that are currently accurate and suggesting they must be working fine. If you select for people who accurately predicted the last year you then need to look at their predictions of every prior year.