Teams Channels Policy – ThreadedChannelCreation Not Honored

We have noticed a change in behavior with the ThreadedChannelCreation parameter in Teams Channel Policies.

Previously, setting ThreadedChannelCreation = Disabled in the Global policy prevented users from creating threaded channels.
Since the end of August (coinciding with the rollout of the new threaded channel experience), this control no longer works.
Users assigned to the Global policy (with the parameter set to Disabled) can still create and edit threaded channels.

Microsoft documentation also flags this parameter as “reserved for internal Microsoft use.”

Question:

Has Microsoft removed customer ability to control threaded channel creation at the tenant level?
If so, is there an alternative or roadmap for reintroducing this control?