Basically, if the cost of housing is rising, but the quality of housing is also rising, then these things will offset to a degree as far as CPI is concerned.

It’s one of the reasons healthcare inflation is so absurdly underrepresented. CPI basically assumes that you could pick any level of quality for a good or a service since the index inception. But you can’t go to a hospital and say “I just have a small cut on my finger, I’d like the 1950s level of care”…you will get the 2021 level of care and 2021 prices. But CPI will say “ah that’s not necessarily inflation because the quality of care has also gone up!”