OK. I think I get it. So people enable uPnP on their routers and then open Minecraft’s port using uTorrent (or any other program that opens a port with uPnP). And they do all of that instead of just logging into their NAT routers. Honestly, sounds like something I would do before I knew networking concepts, though if it were explained to me it would be a million times more confusing than just learning how to configure NAT.

Can you explain this? I have so many questions.

This is hilarious because I can attest to this. I took a class where we were partially graded on security - part of that was proper SQL parameterization. Half of my team couldn’t / wouldn’t be bothered to do so. It was just impossibly hard to get them to do so, almost as if I was asking them to do 10 pushups for every line of code.