This has been happening since launch for most of the people I know including myself. I've put more hours into handheld/portable consoles than placed into my PS4/PC.
I've had many 3DS's for various reasons...and got a Switch a week prior to launch thanks to Best Buy (no games though due to separate shipping...). I still play both even today. The Switch just took any remaining life that was the WiiU and a part of the 3DS.
The few holdouts I know that are still with just the 3DS is mostly due to a main Pokemon series not releasing on the Switch yet. While a few others won't get a Switch until a Mini version comes out... I think a large contingent of those types of gamers will migrate over once their favorite series releases.







