In the bluetooth settings it literally states: "To improve device experience, apps and services can still scan for nearby devices at any time, even when Bluetooth is off." This can be completely turned off in scanning settings. The article title is kind of clickbaity.
I wonder, what apps and services it helps improve? Why would you want to turn bluetooth off but not really turn it off?
Now, sure, I'm sure the response of the people here is "But I turned it off because I want to have to use settings to turn it back on." And that's fine. But that's not the use case for most users, I strongly suspect. Having a phone that just works with crazy kitchen gadgets is something of real value.