Some of the standard picklist fields in Salesforce have their values defined in Standard Value Sets. This means when you add a new value in the Salesforce UI, for example in the Type field of the Case object, that you are actually editing the CaseType Standard Value Set and not the Case Custom Object.

Gearset detects all these differences, but it isn't obvious why Case.Type appears as unchanged in a Gearset comparison. It would be better if Gearset showed some help text in the Case.Type object definition that pointed me to some help docs or linked me to the exact CaseType picklist that I'm almost certainly looking for