There's something very off about this story, especially since it doesn't even attempt to mention obvious scenarios like "what if I have WiFi turned off?".
If iOS would actually try to find WiFi networks with WiFi turned off, that would be a much bigger story than some exploitable vulnerability. This whole story smells of sensationalism over facts.
Not necessarily. Android has an option (which is on by default) where Wi-Fi off really means off except for location assistance. If iOS has something similar and the issue even affects that passive scanning, it could be a deeper problem. I wouldn't say that's likely, but it is possible.
I don't actually know how iOS deals with this, but judging by the fact that iOS says "turning on wifi will improve location accuracy" when wifi is off makes me think it's really off for all purposes.
If iOS would actually try to find WiFi networks with WiFi turned off, that would be a much bigger story than some exploitable vulnerability. This whole story smells of sensationalism over facts.