I have lived and worked in some of the most horrible, manky, poor, deprived, crime-ridden areas of my country. I have had people try to walk into my house past me, and have had physical threats against my person. And not once did I ever think "What this situation really needs is another gun".
You might be surprised to know that most people who own guns don't think of them as the answer to every confrontation, in my experience. In fact, in all of the training I've received has emphasized that bringing a gun into the equation should be the last resort and should only happen if you fear for your life or for the safety of others. Some dude threatening to pummel me wouldn't do it. Some dude trying to rob me wouldn't do it. Even some guy in my house stealing my TV wouldn't make me shoot as long as he didn't look threatening (although I'd certainly keep my gun handy and my family behind me while we wait for the cops). I can't see myself pulling the trigger or even aiming a gun at somebody unless they clearly pose a serious threat.
I can't emphasise it enough, if you point a gun in my direction, accidentally or not, I will do anything up to and including killing you to stop that situation occurring or continuing.
Luckily for the other party, you wouldn't be armed so there's not much chance of you being able to do anything about it if they were pointing a gun at you.
But owning a gun expressly for that purpose will only cause the same reaction from the other party.
I guess if a person owns a gun expressly for the purpose of pointing it at people then, yes, at some point one of those people might be inclined to aim a gun back at them and possibly pull the trigger. Maybe I'm not understanding what you mean by "expressly for that purpose". The "purpose" of self-defense guns is to protect the innocent from serious harm. Like the concealed-carry permit holder in my area that drew his gun to stop a guy who was stabbing random people in the parking lot of a grocery store. The gun-owner held him at gun-point until the police arrived. Personally, I sure am glad he had a gun.