It's all over - just search for ipad pro tandem oled
Like here:
This is not RGB?
As for the text the tandem OLED not being a pure RGB layout will make the text less distinct/sharp.
Apart from the question of RGB (or not), the proof is in the pudding and text on the M4 iPad Pros is tack sharp. As I said, I have both at the moment and text sharpness is identical to my eyes, if not better on M4 because of the higher contrast.