Deleted - Oh yes this is a.o. the various things I performed. btw, https://support.microsoft.com/en-us/help/4022522/dcom-event-id-10016-is-logged-in-windows-10-and-windows-server-2016is really a joke :
[...]
You may change the permissions on DCOM components to prevent this error from being logged. However, this workaround may have side effects. It's better to just ignore these errors because they don't adversely affect functionality.
[...]
If this is not an error, this this must be logged as Warning but if this is an error, this is not to be ignored. How shall one then distinguish real errors from fake ones.
Recovery option is not... an option : I cannot be at the risk of recovering my PC upon every feature update.
I managed to go down to a few errors (The application-specific permission settings do not grant Local Activation..., Windows cannot load the extensible counter DLL rdyboost..., Timeout waiting for iSCSI persistently bound volumes..., Initiator failed to connect to the target...,The initiator could not send an iSCSI PDU...) and solve the performance issues.
This is very bad omen for professional deployment of Windows 10 though