There is a 50 character limit on the SQL Server Name when creating an MCS profile for SQL server. This limit did not exist for UIM 20.1, MSC profiles.
This is the OC screenshot while creating the SQL Server MCS Profile -
In the "Server Name" field, more than 50 character is not allowed.
After checking the code, this is confirmed that - there should be a 50 character limit on the "Server Name" field, even for 20.1. And, that limit exists for 20.3 as well. Somehow, the older versions might have accepted more than 50 characters for this specific field, but there was a limit from the beginning.
Component : UIM - MON_CONFIG_SERVICE
The 50 character limit on the SQL Server Name for an MCS profiles is per design. This is not a software defect, and there is no current plan to increase the limit.
Defect DE489849 was created to confirm this 50 character limit on the SQL Server Name for an MCS profiles on OC 20.3.X.