Some 17,500 fatbikes imported from China have been held by Dutch authorities over concerns about speed manipulation and safety risks.
There is a link to the article without paywall somewhere in the comments, but yes, the image is a wrong one (or actually a real, non electric mtb fatbike). The “fatbikes” we have here in the Netherlands look like this:
I don’t see a paywall, it just does not contain anything but the stock photo. Your example looks more like a moped, which is indeed a motorcycle and should fall under the same regulations.
The problem the government faces is how to make a distinction between moped and a classic e-bike. Because from the factory there is no real difference apart from “oh it looks a bit like a moped”. My vote goes to setting the minimum age for assisted riding at 16 (except medical reasons) or at least obligating having a helmet under the age of 18 (to protect their poor undeveloped brains). Which will immediately kill the attraction which is to ride a moped without helmet. The real challenge is regulating e-bike unlocking in general (as well as adding a throttle). Which is hard because the electronics can quickly be set back to factory with a click of a button.