The more I learn, the more I want this as a 3DS replacement. The TV aspect doesn’t interest me as much. It looks like it might deliver on that promise as they work the kinks out.
I don't know if that's even possible. The 3DS has pretty good third party developer support and a huge back library.
The true worth of any system is how many high quality games are on the system and whether they're the games you want play.
Outside of the obvious "must have" first party titles, I can't see a whole lot of system-selling "must have" third party titles. If you're not into Nintendo's own games, you pretty much have no compelling reason to get a Switch. And if Switch hardware sales aren't strong enough, third party developers will stay away.
It also doesn't help (especially for parents on a budget) that Switch games are around $20 more than 3DS games.
Fire Emblem also traditionally had home console releases alongside portable gamesystems, but the Wii U flopped too hard for niche games to have much room. Concentrating developer efforts on a single console that does both portable and home, large screen play is a smart move for Nintendo.
For example, I like fighting games, and that's why I bought the 3DS (even though you can count them all on both hands). Street Fighter IV was one of the early launch games for the 3DS and holds up surprisingly well.
Meanwhile in the Switch announcement, Capcom announced a rehash of the older 2D Street Fighter II, which is a less than impressive announcement. At least the Wii U got Tekken Tag Tournament 2.
If I didn't just buy a GPD Win recently (which plays the Windows Steam versions of SFIV and Street Fighter x Tekken among others at close to 60fps @ 720p in a 3DSXL-like form factor), I would still choose my 3DS for fighting games over the Switch for the foreseeable future. I still play my 3DS a lot because I somehow started playing Pokemon for the first time (Sun/Moon) and got hooked on it.
I actually pulled the trigger on the my GPD Win a couple of weeks after being disappointed with the Switch webcast. It basically killed any remaining desire I had to get a Switch, but as I mentioned earlier, it all comes down to the genres you play and which platforms serve them the best.