Are these Netlogon Errors a concern?

We have a Windows 2008 R2 domain functional and forest level and are primary FSMO role holders are Windows 2008 R2 Servers.  We have introduced Windows 2016 DC's and are checking health so we can move FSMO roles.

I've noticed running DCDiag on the Windows 2008 systems give me a ton of Netlogon errors but I don't see this on the Windows 2016 Servers.

            Event String:
            The Netlogon service allowed a vulnerable Netlogon secure channel co
nnection because the machine account is allowed in the  "Domain controller: Allo
w vulnerable Netlogon secure channel connections" group policy.
         A warning event occurred.  EventID: 0x000016C6
            Time Generated: 05/04/2021   09:26:59
            Event String:
            The Netlogon service allowed a vulnerable Netlogon secure channel co
nnection because the machine account is allowed in the  "Domain controller: Allo
w vulnerable Netlogon secure channel connections" group policy.
         A warning event occurred.  EventID: 0x000016C6
            Time Generated: 05/04/2021   09:27:44
            Event String:
            The Netlogon service allowed a vulnerable Netlogon secure channel co

Should add, running the standard repadmin/showrepl and repadmin /replsummary does not show issues.

Googling a bit, I've seen some things indicating that Sysvol isn't replicating properly, but I do see it on the Windows 2016 servers and Windows 2008 R2 servers are the primaries.  I have also read that this isn't an issue.  Or is this rather a Group Policy issue?

We are trying to do our due diligence to make sure AD is healthy before we move FSMO roles.

Thanks