Absolutely correct. And having 2 consoles in the same generation is not unprecedented. Magnavox had 2 consoles in the first generation, Atari had 2 in the second generation, Sega and Atari both had 2 in the 3rd generation and SNK had 2 in the fourth generation. It's less common now but it's certainly not something unique to Nintendo this generation.
Too many people think power determines their inclusion into a generation but nobody in the industry itself has ever used that criterion.
None of what you two guys said matters.
Nintendo issued a press release based on NPD data, and NPD has classified Switch as a current generation home console. Nintendo isn't going to bother to contest that classification, they just take it and build their PR from there.