Prefab Variant is not created when using PrefabUtility.SaveAsPrefabAsset

Reproduction steps:
1. Open the attached “BugRepro” project
2. Open the “Assets/Scenes/SampleScene.unity” Scene
3. Select the “Bug-CreatePrefab” GameObject in the Hierarchy window
4. Click the “Create Prefab Variant” button in the Inspector window
5. Observe the Console window

Expected result: “Original prefab type is: Regular” and “New prefab type is: Variant” are present and Prefab Variant is created
Actual result: “Original prefab type is: Regular” and “New prefab type is: Regular” are present and Prefab Variant is not created

Reproducible with: 2021.3.37f1, 2022.3.24f1, 2023.2.18f1, 6000.0.0b15

Reproducible on: Windows 11
Not reproducible on: No other environment tested