Yeah, pretty much this. We like to compare PE to regular exercise a lot, but it’s really quite different. If it worked the same you would basically just flex all the time and eventually be as big as a body builder. Please, nobody bring up any comments about isometrics in regards to my comparison :)
If you got a 1.5” fat pad and are surely overweight, dropping body fat is a sure way to reduce your fat pad, and increased the exposed amount of penis. Plus its pretty common that your erection will be stronger and better eq when you are are closer to a weight ideal for your size.