It seems like these days there's a big deal over pistols being "Fully Ambidextrous". Law enforcement agencies want their pistols to be able to be configured for the lefties in their department. Well, lefties shouldn't be in law enforcement g'damn it! I'm kidding of course. I think having pistols configured for left hand or right hand shooting is unnecessary and a bad idea.
Save for a manual safety, all pistols are ambidextrous. Take a Glock for example. On a Glock there are 3 things you need to do with either hand.
1. Pull the trigger
2. Drop the mag
3. Chamber a round
The trigger is obviously ambidextrous. The magazine release is what everyone wants to be ambidextrous or reversible. But wait, when shooting a pistol with an American style mag release (on the left side of the grip, rather than on the heel of the grip) you can easily manipulate the mag release with your trigger finger.
Many people also seem to want the slide release to be reversible as well. But the slide release isn't really intended to be used to drop the slide and chamber a round. In fact it shouldn't be called a slide release at all. Glock calls it a "Slide Stop" for this reason. The best way to train chambering a round with the slide locked back is to reach over the top with your support hand, pull back and release. Guess what? That's ambidextrous! You can do it with either hand.
I don't necessarily think it's a bad idea to have a pistol that's always ambidextrous. But I do think it's a bad idea to reverse mag catches and slide stop levers. Picture this. You are at an active shooter scene. There's a cop or security guard that's been shot. You pickup his pistol to defend yourself. If you are a lefty and you train with your lefty setup pistol (that you apparently left at home), you will not be able to manipulate it under stress. The same problem applies to a right handed person who picks up a pistol setup for lefties.
Both right handed and left handed shooters should practice manipulating a standard configuration pistol with their strong AND weak hands. You probably already practice weak handed shooting. Now learn to work the pistol with your weak hand as well.