First, the arithmetic in Spoke Calc is rounded off. Let's get it right.
The 24:11 ratio = 2.181818....
The 38:18 Ratio = 2.11111.....
So, the 24:11 is about 3% lower than the 38:18, and therefore is in fact easier.
Now with that said, if the real ratios were identical, there would be no difference in pedal force. The longer chainring lever length on the 24:11 is offset by the shorter lever length on the 11 tooth cassette gear. The analysis that the true measure is the wheel inchs per pedal revolution is the correct analysis. In the real world, there is a tint difference in the force required caused by friction differences between the two different combinations.
There, now go ride your bike and pedal however feels best to you.