That is the certificate I earned upon completing community college. Their Linux curriculum was originally designed around Debian, but when IBM acquired RHEL, redesigned to offer this foot-in-the-door.
IBM still seems to do alright in the legacy mainframe/mini market. It is quite strange how the AS/400 and zOS stuff all goes without notice of ordinary IT guys like me, as if it didn't exist, but still powers a lot of machine rooms that aren't AI data centers.
When you need to do fraud detection with extremely low latencies, this is the way to go.
Part of the value of a migration would be the opportunity to to unwind some of the details that are contradictory, mis- or non-documented, or wrong-but-unfixable.
Also, a lot of the problematic issues are related not to fixing the local code, but dealing with stuff like external systems or pre-existing legacy data that you need to be able to read back after 30 years from cold storage.
Good news, it did not. It is worse.