The link you added to the HPCBike actually looks far more like an bike than many of the much slower class 2 e-bikes that are sold. Appearance isn't that helpful when it comes to enforcement or crafting regulations.

It is, however, a great example of the kind of device being discussed in the article. Sold as a "class 2 e-bike" but with a software toggle to let it hit 70mph at will. However, I would argue that in many jurisdictions (such as Connecticut) it still doesn't legally qualify as an e-bike even with the software limiter because it has a >750w motor.