Unfortunately Goodhart's law has rendered official inflation measures borderline useless, as anyone who has been shopping for food for the last decade can tell you.
Are CPI measurements difficult? Sure. It takes a bunch of expert eggheads and a lot of shouting to come to consensus. Still better than trusting some kind of magical commodity market to tell you.
Not to suggest CPI is redundant, there's a reason why central bankers read it after all. For one, it's the most timely data they have. But it's impossible to nudge it year after year -- accumulative error -- without it become obviously decoupled from other data, including the long-term bond market data. It just so happens commodities are the wrong yardstick.
easy to explain. Gold has a supply constraint. More demand causes prices to rise. When you have a currency following a heavy inflationary trend, people buy Gold, so the price of Gold goes up.
There are a shocking number of gold-happy nerds on this site who are going to be shocked and horrified the next time it crashes (which is has, and will again). The nonsense the largely-partisan smarter-than-thou media you're watching is feeding you is nonsense, and at some point you're going to discover that via great suffering.