I do not agree. The screen is already so small, 720p 237 ppi looks much thinner than 1080p on TV, and then it's connected to me on 32-inch TV. Step up to the 1080p LCD screen would be wrong, games should be further reduced in terms of graphics, and the end user could hardly make the difference between 1080p and 720p.
Also OLED is far from ideal, the peak of illumination is very low in such screens compared to the back cover LCD. For example, Vita can hardly be used for daylight, you really do not see anything. OLED also consumes more power than the LCD.
Now, OLED displays with better brightness are always better, but you will not see them in a relatively cheap console. Nintendo should be particularly nice on 720p and LCD. Cheaper, barely visible difference from 1080p, higher light and less energy consumption.