Um but Ninty has been using the same scheme since forever, haven't hey? They keep changing the colors but A on the right and B on the left has always been there.
It's Sega that reversed it (or maybe it was the other way around, I dunno) and then MS copied that layout, again with their own colors. Sony has always had their own symbols.
While the reversed A/B is kinda silly, at least they are immediately distinguishable, unlike the pink square / red circle, where every QTE screen prompt gives me a bit of a pause.
Anyway, just looking at the images of various controllers - funny how the SNES variant with color buttons, Xbox and PS each have a blue X on different position, and then N64 has a blue A, Dreamcast a blue B and there's a Saturn variant with a blue C, each one somewhere else. That has to get quite crazy when one uses multiple consoles. I only have 2 of these and it usually takes me a while to adjust.
Still better than touchscreens though.
Edit: Or do you mean Ninty used B for advance and A for backwards before and not anymore? I dunno but when I goofed with N64 and GC emulators back in the day, I think the controls have always been reversed compared to the Xbox/PS conventions. I always ended up just remapping the controls according to letters of the X360 PC controller regardless of where they are on the original controller.
It reminds me of a fun story. A long time ago I played FF7 in a PC PSX emulator, but the control scheme was garbage so I remapped the buttons directly in the game (ah the times when console games allowed button remapping). I wasn't familiar with the PS controllers at the time (I didn't have a console but I did buy those PS games btw) so I often had to peek on a photo of the PSX controller to make sure I'm pressing the right buttons. But then at one point there was that piano minigame which ignored the remappings (i.e. it showed incorrect prompts according to original button positions) so I had to map the buttons in my mind from my remapping to original buttons to the X360 PC controller all while trying to follow the QTE prompts Good times I guess.