We are experiencing the same problems - AGAIN - with 2021-10 Cumulative Update for Windows Server 2016 (KB5006669). Farm with Windows Server 2016 / RDS + Citrix 7.15CU8. Microsoft Print to PDF is required by one of our published applications. We already rebuilt the entire farm before because of the same problem with previous updates.
Uninstalling 2021-10 CU does temporarily resolve the issue but that's obviously no valid solution - especially not on a host used remotely by a lot of users.