I think the Switch OLED was the planned Switch Pro, but they changed the plan to include the 2019-chipset from the Switch-Revision and not a new chipset. All other features would have been great for marketing of a pro-console.
The positive things a Switch Pro would have had:
- Games would be already optimized to use dynamic resolutions up to 4K when Switch Two launches
Bad things about Switch Pro:
- Would have made the Switch lifecycle even longer. Six years will be completed soon and the Switch Pro really could have made the ten-year-lifecycle-dream they said they believed in a reality
- Developers would have had at least one more tier to optimize for and most likely wouldn't make ports which would only run on the pro-console.
- It would be hard to advance from a Switch Pro before…lets say 2025. The mobile form-factor makes it much more difficult to achieve a generational jump without making the device to big or heavy in a time almost all chip-companies increase their power-usage.
I think a new hardware is the better way. Make the Switch-Hardware better with a longer development-cycle than the WiiU-Crisis-Cycle we had last time. Do cross-generation for two years until you have a Lite-Version of SwitchTwo to make easier update-paths for people with less budget. Give attention to more small titles in the Nintendo Directs which also run on the old Switch. This could be a smooth transition if done right.