Validation errors during Change Set rollback after required field addition

A deployment via Salesforce Change Sets introduces a schema change that adds a new required field to an existing object. While the platform provides a built-in rollback mechanism to revert configuration changes, the presence of this required field creates a conflict when attempting to return to the previous state.

The primary constraint is the potential for validation failures if the rollback process cannot reconcile records that were updated to satisfy the new requirement. There is uncertainty regarding whether the platform handles the removal of the required attribute without triggering field-required validation errors on existing records, particularly across different API versions (e.g., API 58+ versus older versions).

• Does the rollback process automatically bypass validation rules when reverting a required field to optional or removing it entirely?
• In what specific scenarios does a schema-based rollback leave orphaned references or inconsistent data states that require manual cleanup?