Hi Daff,
Microsoft does not describe this as a Windows Server 2019 “block” so much as a Windows Server 2016+ design change. In Microsoft’s RCM documentation, they state that starting with Windows Server 2016, Remote Connection Manager no longer queries the user object in AD DS. They also say that on an RDSH server, the attributes on the Remote Desktop Services Profile tab are not applied, and a user who relies on those settings will fall back to a local profile unless legacy RCM behavior is enabled.
The legacy behavior can still be re-enabled by setting fQueryUserConfigFromDC=1 in the documented registry locations, which is Microsoft’s way of restoring the older model. So the AD user-object profile path is not the modern/default path on Server 2019; it is the legacy path that is ignored unless you explicitly turn that behavior back on.
The Group Policy setting “Set path for Remote Desktop Services Roaming User Profile” is still documented and supported for RDS connections. Microsoft says it applies only to RDS connections, and that the RDS roaming profile takes precedence in an RDS session.
Therefore, the AD user-object “Remote Desktop Services Profile” method is legacy and not used by default on Server 2019 RDSH; the GPO-based RDS roaming profile setting is the supported method; and User Profile Disks are also still documented for RDSH/VDI scenarios. Microsoft’s docs put the key limitation in the “Changes to Remote Connection Manager (RCM)” article and the GPO behavior in “Set roaming profile path for all users”.