A lot of rounds real fast. Some people enjoy that. I don't. But I see it done often enough. Many firearms ship with standard magazines of 15 rounds or more.
Aside from that, I am sure that you can understand how someone shooting for time would want a larger magazine. Fewer reloads may save a second or two.
Why - what do you think the primary purpose of a "large capacity magazine" is?
What is the problem with semi-autos? Too fast for you? What do you mean "falsely called"? That is the proper terminology - adopted around the world. The single most common handgun platform worldwide. You want the whole world to bend to your will?
"Single shot automatic cycle weapons"? That's a good one. Did you dream that up yourself?
I'll give you my take. A semi-auto saves you the trouble of having to chamber a round with every shot. Fer chris-sake - even an 1800's vintage revolver rotates the chamber to the next round. More rounds in less time is technology that has been engineered and developed since well before WWI. And you want people to go back to single shot pistols? Semi-auto's are popular because of the functionality.
To be sure - the precision single shot bolt fed rifle is an art form. It is capable of being supremely accurate and used to be the choice of military snipers the around world.
But for the average Joe, a semi-auto pistol for self defense is the way to go. You might not need to use it for that, but you will darned well wish you had it if you need it. I can pretty much guarantee you that no one ever found themselves in a self defense situation and said "I wish I had less ammo and a single shot pistol".