Disallow changes to managed wifi networks on supervised devices

I noticed that users can modify wifi settings and save those settings permanently even though the devices are supervised and the network is configured with a profile that is sent by mdm.

this is true for devices with a single user, as well as for shared iPads. Even a guest that logs into a shared iPad can go to the system settings and change the settings of our organisations managed network to use any static ip address. that is a little bit crazy to me.

I contacted the mdm and they acted surprised too.

Is this a design decision from apple or by mistake?