Considering that your claim had been "Proportionally the number of people with intentions to hunt and fish are smaller than they were then", I think it is pretty disingenuous to claim the number 15.7m is the relevant one. (That appears to me to be the figure for hunting alone; fishing is more than 44 million as indicated by both the graph and the text of the article.)
Considering I said proportionally I stand by it. More people out of the total population likely fished in their daily lives in 1790 than 2017, because the 1790 population was almost 99% agrarian and rural.
If I was talking about absolute numbers, that would be a different matter.