OK, I've gone back and read through the whole debate. Basically, you fell into a Jonas trap and some side arguments sprang up and now we're debating lots of little stuff that doesn't really matter and we're all basically on the same page except for Jonas who kinda lives on his own island and does his own thing and no one's ever really sure if he's trolling or playing it straight.
I agree with you: It's rare that a natural winger converts to center at the NHL level and it's even rarer -- bordering on unheard of, at least in today's league -- that the conversion produces an "elite, elite" centerman. And there's a very good reason for that, as you noted.
I do think it's fair to say Lafreniere has qualities that suggest he could have a future at center. That's not an especially controversial idea. But I think it's also fair to doubt there's anything to that notion and to say it's all moot because you're getting a superstar winger and there's no point in trying to fix something that is the exact opposite of broken.
At the end of the day, I just want a Lafreniere-caliber player. He could be a winger or a centerman or a defenseman or a goalie -- I don't care. I just want a gamechanger. If we get Lafreniere and Yzerman and Blashill (?) are like, "We feel he belongs in the middle," I'll go along with it. I'd expect them to drop it the second it starts to look like a bad idea, because I agree that there's no reason to run that experiment unless you feel the guy just flat-out screams "stud pivot."