Here's my problem with this "update every 2-3 years" idea; I don't want games in 2020 and 2021 to run like shit on my base Switch. I paid $479 for my system, I want at least a good 5 years of support from it without being forced to buy gimped, choppy versions of games that come out after the Switch 1.5, fuck that shit.
Switch was behind Playstation/Xbox/PC from day one though, so people have already accepted that its not graphically competitive, they knew that when they bought it. As such, I think that's a pill the general audience has already swallowed and that it falling even further behind visually just isn't a big deal.
Nintendo can't run their entire business based on your needs.
It's not your ass on the line when (like it does 50% of the time for Nintendo) the next platform transition back to 0 goes badly for Nintendo.
If I'm the Nintendo president I have to look out for my business first and foremost and I'm not taking that risk of a hard reset to 0. With only one hardware line (no GBA/DS/3DS to fall back on) and no other major divisions like Sony/MS have ... fuck no.
It's not like OG Switch gets 0 games and is rendered completely useless even if they do the 3-year cycle. Most/all Nintendo games can still run on it, and so could the same exact indie/third party games that were going to come would come anyway. That's likely still hundreds if not thousands more games coming to that model of Switch.
It would just likely mean initially there might be 5-15 third party titles a year that run on the "Pro" model that simply would not be possible on the regular Switch, and then by 2021/2022 you can have a more phased transition where maybe that increases to 20-25 games a year.
IMO that's fair all around.