Full disclosure: I haven't watched the video so what follows may not even address what it talks about. I'm just shooting the breeze here, killing time before I have to go to work.
10mm vs .45 ACP.
Both seem to be using a sledge hammer to drive 16 penny nails.
In 99% of cases, a .22 will get the job done when it comes to getting the typical bad guy to stop doing whatever it is he's attempting to do and .40 getting close to being more than anyone would need for personal defense against nearly any human bad guy. Anything between those two is going to get the job done pretty well.
10mm or .44 magnum makes sense for defense against bears and basically nothing else. They're just too much gun for the vast majority of self-defense situations.
.45 ACP is fine if that's what you like but you can get virtually all the same work done with a .40 or even 9mm if you select the right ammo.