Sean Gallardy isn’t too concerned about self-signed certificates in SQL Server:
This happens at startup and is completely transparent to both end users and administrators alike, apparently not so much to your security team utilizing the latest and greatest security tools available (yes, that’s sarcasm). One day you may get a notice that “SQL Server is using a self-signed certificate (issue #1) and that the key length/algorithm isn’t what our internal security team allows (issue #2). You must fix asap or be out of compliance!” Oh no, the dreaded compliance threat.
Sean is…not impressed with these issues and explains why.