Something I've thought about a bit. I'm no opponent of quality adjustment, but one issue is that you generally don't have the option of buying the lower cost items of lower quality as time goes by. https://wolfstreet.com/2019/02/13/sticker-shock-prices-of-new-cars-trucks-flat-for-22-years-says-cpi-even-as-the-price-of-a-taurus-jumps-55/

So while quality-adjusted inflation may be low, your actual nominal expenditure on a lot of items has still increased substantially, whether or not you would have picked the higher quality versions when given the actual choice.

That is, say for the sake of argument you need a new car for the lowest possible cost, and would prefer cost savings over quality. Well since you can't make that trade-off, you're locked into a much higher car cost inflation rate than what CPI implies.

And if your wages increase according to the standard, quality-adjusted CPI but your actual expenditure has to increase by more than that, you have a problem!

I think this probably isn't an existential threat to the CPI because most things aren't like buying vehicles. You can buy fewer, better quality small items, or actually lean toward more expensive but better quality purchases. But it's something to think about.

This thread inspired by this article, although I'm far less harsh about it (see last tweet). https://www.ianwelsh.net/bullshit-economic-statistics/