Now if Google could explain why toggling wifi through Tasker requires root, I would LOVE to hear the reasoning…
tbf all hardware-functions require root permission by default.
Linux does the same thing. If you want to access /dev/sda, it requires root.
I could guess one of the ways it could interfere with security is that it would probably also allow the app to disable WiFi. If the app does that, it could incur costs as now data is being transmitted over mobile connectivity. Also, it would maybe allow the app to find your mobile-IP address, which could be used to geotrack you. But i don't know, i'm just talking out of my ass here.