After unlocking the developer options on the OnePlus smartphone, we can turn on/off USB debugging at any time.

USB debugging is required if the user wants to redraw the device or install custom-roms.
The function is also required by the MyPhoneExplorer application or program, for example, to synchronize contacts.

Note: A permanent activation of USB debugging is not recommended, as external access to the system would be possible in case of loss or theft.

Android 10 | OxygenOS 10.0
USB Debugging -  Open the  Settings
USB Debugging -  Tap on  System
USB Debugging -  Tap on  Developer options
USB Debugging -  Enable or disable  USB debugging
USB Debugging -  Confirm with  OK
  1. Open the Settings
  2. Tap on System
  3. Tap on Developer options
  4. Enable or disable USB debugging
  5. Confirm with OK

OnePlus Instructions