Is the check in this line still valid? I don't know about impersonation, but delegation should work, and it works for us via gssapi (linux client -> windows server scenario).

https://github.com/dotnet/runtime/blob/main/src/libraries/System.Net.Security/src/System/Net/Security/NegotiateStreamPal.Unix.cs#L36