Who configures MSI and other SIs and how the "system" updates that information?

Hello 5G experts, please help me with the following quick questions:

I understand how the UE uses the MSI to access and connect to the 5G network, my question is who/how the MSI and the other SI are configured and updated?

Is the 5G core network responsible to configure and updated based on the phone reports?

Or a RF engineer has a bunch of configuration files/scripts with remote access to each cell and updates the MSI and the other SIs?