I was kind of shocked to see the hours were so low for NH until I noticed this thread was from 2020 during launch. I actually never looked at my hours. My NH hours wouldn't really be too accurate because I would just turn it on, go to the beach area and fall asleep to the ambience. I worked so many hours that year it was a blur and the game helped me fall asleep.
I think my most played Switch game is AC:NH. I haven't checked the numbers for myself, but I have about 1000 hours sunk into it since I started playing in July 2020. Breath of the Wild is close with ~600 hours, which is also my most played Zelda game. Most Switch games I've played have under 100 hours into it, and the only other game with more than that is Miitopia, with 135 hours.