It looks like the majority of Nintendo Switch owners in the United States also own another console aside from just having the single platform. This information was provided by Mat Piscatella, Video Game Industry Analyst of the NPD Group. It was collected through PlayerPulse.
The first aspect to note is that 30% of the player base only has the Switch as a console. This is followed by 31% that have a Playstation 4 in addition. A comparison to the 23% that have a Xbox One with the Switch. The final note is that 17% of owners have all three of the consoles.
That means the vast majority have another platform they game on, leading myself to suggest that they use this console as an accompanying system. The quantity that only have the platform either choose to do so, or are also coming from the mobile side being 3DS models and such. You can read about new Animal Crossing details, or the general platform hub for additional coverage.
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