I am unsure what the future of Nintendo handhelds are.
I feel the same way. The only system to sell more units in 2016 than 2015 was, of all things, 3DS. Pokemon Sun and Moon were the best selling Pokemon games in the last decade. Pokemon had 2 spots on the December NPD top 10 during the all important Christmas season. All of that makes it seem as if there is still life in the ol' 3DS yet, so one has to wonder what Nintendo does with that, obviously still successful, leg of their business. It'll be hard to give up on it if the Switch moves only Gamecube or, worse, Wii U numbers. However, the whole point of Switch was to be able to stop splitting their development time between two pieces of hardware. Add to this that their mobile games kind of compete with their own portable market, and it looks like a bit of a difficult decision in their future. If I were them, I'd keep trickling games out for 3DS just in case I needed to backtrack and make a 4DS eventually.