Inflation isn't a scalar, which is the main point of the article. The problem is that capturing all prices at all times in all locations is effectively impossible, so it's generally oversimplified out of necessity.
On the other hand, the value of a Dollar...
The Morgan Silver Dollar from 1901 that I keep with me as a reminder, is worth about $17.50 in melt value.[1] The folks my age and younger generally don't appreciate the value of hard money.[2] It's almost always bought about 4 gallons of gasoline, or a meal for one. Say what you will about the inefficiency of a commodity backed currency, it won't shrink to zero value over time.
[1] https://www.coinflation.com/coins/1878-1921-Silver-Morgan-Do...