I just noticed this with the 5ghz SSID on my iPhone.
This network is blocking encrypted DNS traffic. The names of websites and other servers your device accesses on this network may be monitored and recorded by other devices on this network.
What's going on and should I be concerned? Surprisingly, I don't see this warning on the 2.4ghz SSID.
I don't know how to generate a backup within Luci.
The funny thing is that the 2.4ghz SSID doesn't have this privacy warning. Only the 5ghz SSID has it. It's not like the GL.iNet GUI has settings specific to the frequency so I don't know what is causing it.
Please try resetting the router firmware and use laptop to complete the initialization wizard (change a different SSID and password than before), then test it again with iPhone.
Seems we did not reproduce this issue, you can recall what you've set up in router, and enable it one by one in router, observing the iPhone's WiFi connection.