The Wii, DSi, 3DS and Wii U all had both physical media and downloadable software. There were e-shop exclusives for all of those systems from mini-games to obscure games that were localized from JP and were too niche for a physical release.

Every current system, and the last several Nintendo systems, have had physical media and digital purchase options. That the system accepts physical media tells us nothing.

That's far from likely. Not having digital purchases would be a terrible decision for a gaming system. The slot will be there to allow the choice to buy physical media, and to placate brick and mortar game stores.