The purchasing power of $3.05 in 1914 would require $100 in today's time. A bag of "stuff" worth $100 today could have been purchased for $3.05 in 1914.

Technically, it does mean that $3.05 from 1914 is worth $100 today, but that's not a useful way of thinking about this. I.e., if your great-grandfather put $3.05 in an envelope in 1914 and you opened it today, it's still $3.05 worth of money (ignoring wheat pennies being a collectors items and whatnot).

I'm pretty sure you are right. Or to emphasize the devaluation, "$100 today would be worth only $3.05 in 1914."

I think it is astonishing that we accept that in a best case scenario of sustained 2% inflation, we are literally planning for the value of the dollar to be cut in half every 36 years.

Yeah, they must have gotten it the wrong way around.