Adaptation by us "main gauche" folk has been a part of our lives and it allows us to instinctively complete tasks that "main droite" folks don't even have to think about. Being adept, through adaptation, of using right handed implements, can mean survival. Even the task of writing a sentence in English is designed for right handers. Left handers have to modify the way they write to keep from dragging their hands through the ink as they progress. That's why ones sees the oddly arched wrist or pads at such "wierd" angles for lefties.
Same goes for using almost any tool, among which our AR's are included. I have left handed bolt rifles, but I grew up on right handed ones and it makes no difference to me which I shoot. In the event I have no access to "my" custom tools, I can do quite well with the ones at hand.
My main point is that those of us that are lefties, already adapt to the right handed world in many ways you righties don't even realize. Many of us are ambidexterous, doing things with either hand or even some tasks righthanded only. Ever watch a "rightie" try to use a left handed rifle or those scarce other "leftie" designed tools, or even use their left hand to perform a task they easily perform right handed. It's FUN for us to watch them.
They look so... awkward!
Given the luxury of time and money, yes, custom designed tools are great. Given reality, adaptation could be the difference of life or death. Waiting until the last minute to do so is not cool.