Why do people care if others buy a Switch or not? And why do they care about the reasoning?
If someone is a huge fan of the franchise, it's not crazy, to them, to invest in the system to buy more installments in their favorite franchise.
If someone isn't as excited about Pokemon, it's not unreasonable to think that other games on the system attract them.
Or, perhaps they're not as excited about Pokemon, but also not about the other games on the system. Then they wait until a significant enough price drop or more games that they are confident they will enjoy come out on the system.
Basically, the decision regarding the purchase of the Switch, as well as the reasoning, should be up to the individual. If they want it, great! If they don't, also great!