Yes, a 5-year-old can play Nintendo Switch, but some games are going to be too complicated, require too much dexterity, or have too much dense text for a 5-year-old to enjoy. In general, avoid games that require fast reflexes like platformers or shooters, games with complicated narratives like RPGs, and, of course, watch out for inappropriate content. However, something like Clubhouse Games or Animal Crossing is perfectly palatable for an anklebiter, assuming their attention span and reading skills are up to snuff.