I'm an older guy, and I decided to get a Switch a couple months ago. I never owned a Nintendo console before, but over the past few years, I had grown bored with gaming on PS4 and Xbox. I felt very much as if I'd "been there, done that" with most games.
After a while, I realized that I wasn't tired of gaming per se, but of the types of games that were being produced, and that the solution lie in shifting from the standard mainstream games, with their emphasis on serious/mature themes, violence, and darkness to a more fun and lighthearted style of game. I wanted a game that would provide a pleasant diversion, not be something heavy, serious, violent, and dark. I discovered this while playing SpongeBob Squarepants, of all things, and then replaying Ratchet and Clank.
Then it occurred to me that Nintendo was the one company who specialized in producing these types of games. So I bought one, and I'm really enjoying it. I've got 8 or 9 titles that I'm interested in playing, so it'll probably keep me busy for the next year.
I'll still mix and match. I'll continue to play serious or "mature" games, if I find ones that interest me. But it's great to have Switch as an option. It fills a need for me that no other console does.