Already, there is a defense force.
Look, you probably can find SD cards for cheap, maybe 40 or 30 bucks to extend the room. Given how much one might download if going fully digital, though, maybe needing to upgrade to one that costs 60 or more might be necessary. Regardless, that's an extra price that other consoles don't carry, and some people are already penny pinching to buy this system or don't want to spend more.
Additionally, telling people "not to buy digital" is silly for a variety of reasons. But at the top, I'd list "constraining the consumer" as a big one. It'd be dumb to tell people not to do that when they run out of room on their PS4s and Xbox Ones, and it's dumb to tell them that here. It's a valid complaint about the system, and whether or not it inconveniences you is up to your preference. It's alright for people to air their grievances.
For one thing, Nintendo is calling it a console. It's a console. Stop that. And since these SD cards are so cheap, they could have bundled one in with the machine.
Find me one 500GB game from either of those systems. Hell, find me two games that take up 500GB and force me to buy more memory. I'll wait!