Intune autopilot

We are puzzled by a recent change in the behavior of registering a Windows device with AzureAD. If we set an Autopilot profile and enable AAD join in a tenant, BYOD devices who attempt to just register their device fail with error 80180014. If we allow any Windows device to join AAD, this device will be AAD joined and inherit all policies and apps set in the default profile. The BYOD user needs to explicitly deny to have his device managed by his org to avoid this error.  On the other hand, if no Intune profile has been configured for a tenant and a user opens teams or installs Office, the user gets asked whether his device may be managed by his org and the device gets registered only, not AAD joined.