I expect a "New Switch" to be released sometime in 2021. It's not going to be much more powerful (probably a x2 increase in speed), but it will make the system feel fresher. Currently the Switch has two modes for games:
Mode 1: Handheld play
Mode 2: Docked play
I expect the "New Switch" to be able to play games in "Mode 2" (docked) when playing portable, as that would be a very simple solution for the user. Alternatively, users would be able to play games in "Mode 1", increasing battery life. Nintendo could also add a third mode, a sort of "performance mode", which will increase visual fidelity when playing on TV. But, the revision is not going to revolve around stronger hardware, it's just gonna be marketed as more modern. We might also see a "New Switch Lite" at some point. And knowing Nintendo, maybe an ultra-low-cost revision.
Earlier in the thread people discussed whether revisions improved sales, but that's not the point: Their job is to keep sales at the current level. Hardware gets stale after a few years and revisions help to make things feel fresh again. A revision does not have to boost sales, just extend the natural length of the product lifecycle.
I expect the real Switch 2 to be released in late 2023, so roughly 6 years and 8 months after the Switch. The original Switch will, however, be supported for another fiscal year. Some games could be cross-gen. Compared to other Nintendo consoles the Switch should see high sales at the end of its lifecycle as Nintendo will only have two systems to support during the transition period (compared to a whopping four in the past!), which is why we can't just look at sales trajectories of old systems and extrapolate from there. Looking at data is great, but you also have to take into account the changing circumstances of the present.
