Right now M2 is shrinking while inflation is still positive. That wouldn’t happen if they were strongly positively correlated.

We already see that there is a time lag effect, so does that actually matter?

Anyway, this disagrees with the paper you linked:

https://www.investopedia.com/ask/answers/042015/how-does-money-supply-affect-inflation.asp

It’s also curious (from reading the abstract) that the paper you linked didn’t seem to include money supply in their model? Was that deliberate?

But I’m also just generally skeptical of anything that tries to blame labor or wages for inflation.