> Who cares about inflation if your rent/mortgage is 3 or 4 times higher?

Oh, for sure: inflation is challenging to measure, and it probably isn't very descriptive for a lot of common situations. (I think the Consumer Price Index is an attempt to help solve this issue. CPI compounded about about 2.1% per year between 2000 and 2021.[1,2] The CPI includes measures of rent, but it also adjusts for seasonal changes.[3])

Inflation and CPI both obscure a lot of ground-level realities for people--the nature of all summary statistics is that they fail to capture the totality of reality in favor of giving us a broad sense for what's going on. Anecdotally my folks moved after their rent increased by 50% when their lease expired. (That was last year.) These are obviously nontrivial increases that have dramatic impacts on people.

[1]: https://www.rateinflation.com/consumer-price-index/usa-histo...

[2]: (270.97/172.2)*(1/22.) ≈ 1.021

[3]: https://www.forbes.com/advisor/investing/cpi-consumer-price-...