As far as upgrades to the hardware. How big a leap is it really? You can play Doom on Switch but you can't play it 1080p. I wouldn't imagine upgrading the chip from x1 to x2 is as big of a leap from Gameboy to Gameboy Color, or GBA and GBA SP.
It was speculated 2 years ago that Nintendo might have gone with x2 at the time, but the chip was too new and probably too expensive at the time, and there was maybe some production logistics difficulties, but 2 years have passed. Putting a newer chip in the system might be something nVidia wants. It might not even be cost prohibitive. That is probably the biggest factor. I also don't think that "hard generations" will continue to exist. One of the best thing Nintendo can do is maximize backwards and forward compatibility. If they have minor upgrades to the Switch line every 2 years then they can maintain the Switch line for years and years.
How often do iphones come out? The first iphone came out in 2007. There has been a new iphone to come out every 1.3 years. In the long run how can anyone compete with that? The only thing Nintendo offers over cellphones/tablets is superior games and controls and a decent price. I can't see that being a totally permanent thing though. Upgrading asap might be the only right strategic move. You hear youtube channels praising the switch now and lauding it for it's amazing sales, but I can imagine 2 years from now the same people talking about how terrible it always was and how it was a flop. Nintendo like many other tech companies has to deal with the Silicon Valley mentality of the industry. Even if that mentality is batshit stupid.
Though, one wonders about the reset of Metroid Prime 4. Maybe it was a game being designed for 2 compatibilities and then dropped. Maybe there really was a Switch+ that was quietly cancelled behind the scenes.
As I said earlier, we are due for a revision, but they may solely make a cheaper system. Nintendo is in this weird position where any sign of bad news causes their stock to plummet. "Oh so we sold 17 million this year instead of 20 million" **** like that freaks out investors when it shouldn't. If we don't hear about a revision I can imagine hearing about a big price drop soon. We also might hear about a price drop in the next month. If there is a revision they might hold off the announcement to an e3 timed Nintendo direct. Though, we might not even hear about anything like that even at e3. Nintendo has been lowing the leading time between announcement and release. Especially for revisions. 30-40 days at the most is their current operating procedure.
As for me. I've been holding off buying a Switch until the revision hits. I bought a GBA and when GBA SP came out I was sort of burned. Same with DS and DS Lite. With handhelds I find it best not to be an early adopter.