Neglecting issues due to the war in Ukraine, a lot of the “supply side issues” are not totally isolated from central bank policy, QE, and stimulus. The use of QE and stimulus increased demand, while simultaneously, government policy decreased supply. Now, supply is (mostly) recovered, but demand still remains elevated. Supply can’t keep up, because its target is too high.
This is why we see talk from the Federal Reserve about how consumers will “feel pain” - the only way to reduce demand is to reduce employment or wages, to a level that the supply chain is capable of keeping up with. The Fed press conferences are really interesting to watch as they make this very clear - we are really looking at an “imbalance between supply and demand” due in part to all of economic, social, and political factors.
Also, regarding the CPI not reflecting asset prices: the CPI does not include any measure of equity prices, for instance. Since so many rely on equities to fund their retirement, an increase in equity prices is a meaningful inflation. If the price of the S&P 500 for instance is higher due to an asset bubble, it decreases my ability to purchase shares of it. The increase in equity prices we see is really inflation of equities, but never branded as such. We call it “return on investment”, because the people talking about it are mostly those who already own equities, not those looking to buy them. It’s the same reason as why homeowners dislike seeing home prices increase, while homebuyers enjoy it.
I’ll also mention that the CPI has a lot of other bunk practices in it. For instance, “hedonistic adjustment”. A (slightly conspiratorial) site called ShadowStats computes a modified CPI that uses older CPI methodology (before the meaning of inflation was redefined to show lower inflation) that currently sits at 17 or so percent.