I'd agree that much of that site is opposite to my experience.

The simmering one is particularly odd. All the electric stoves I've ever used work the same way, they have stepped power output (more often consisting of just on an off) and so regulate their temperature by switching on or off (or stepping up and down). The result is they aren't great for simmering, as they typically drop on and off the simmer all the time.

Gas in contrast lets you set the heat output you want and that is what you get.