The corporate/educational store has never been supported in Windows 11 and is being retired in 1st qtr 2023 anyway. Simply having the policy key existing(enabled or disabled) now breaks the store client in Windows 11. I had to set group policy to "Not Configured" to remove the key.
Since shutting off the store is bad for app updates, apparently the best (only?) option to control app access is Applocker going forward.