They will probably lower the price of the 3DS after at the same time.

They also don't target the same population.

3DS targets small kids, it's surdy, and have low graphic capabilities. You put it in their bag back, for a long car ride, etc.

The Switch is a family console. The adults play it. We have diablo on it. But it got only a 3h lasting battery and it's more likely to break.