Sensible? Different states and different parts of states have vastly different costs of living. The average wage in San Francisco is going to be different than rural Alabama. The non partisan Congressional Budget Office estimated that the proposed 2021 increase to $15 would have caused a loss of 1.4 million jobs. (And obviously would have been even a bigger effect 10 years ago.)
>...online inflation calculators say the modern number would be $18.22.
No, that is wrong.
The minimum wage started at .25 in 1938. If it had followed inflation it would be at $4.70.
The last time it was adjusted was 2009. If it had been adjusted for inflation since then, it would be about $8.95.