The benefit of an exe is you can simply keep it on a USB incase it needs installing elsewhere. Also you know for sure it's offline and isn't fickle to a browser history clear out.
But then again its in a usb. Cant really rely on usb ports being open to me or that i wont have to present on a 2017 mac which, unsurprisingly does not have a usb port or on a windows machine i plop in my usb ready to present and all i can present is the antivirus scan progress bar moving slower than san francisco traffic at peak hours. So lets just take print outs to be safe. So much for the effort i put in getting the fonts and colors just right.
Connection-free browser apps have been with us long enough that we can't assume either way.