By the looks of it, Nintendo is just protecting their rear by adding an alert to that appearing on the ESRB, and as the article brings out, it doesn't necessarily mean they will make use of it.
That being said, it wouldn't surprise me if they decided to adopt some of the stuff they have experimented through their mobile application Animal Crossing: Pocket Camp into the game.
You know, I read Nintendo mentioned that while there wasn't going to be cloud saving they were looking in ways to use the cloud, so I am wondering if they are planning to offer, for example, a service so you can store away items in the cloud or some stuff like that. Features that are not needed to play the game, but that would make things easier. Pocket Camp already offers "warehouses" to store items.
I rather not jump the gun. Hopefully we'll get to hear more on how the microtransactions are going to work if they are part of the game.