That's a steerable but non-lockable full-swivel tailwheel, a different thing.
I'll agree with that description though I don't know enough about the subject or met any other type, apart from the free swinging (swiveling) worn out Scot item that I removed before it killed me.
Presumably a "locking" tailwheel would lock straight fore & aft regardless of rudder position, & not "break out" on application of one wheel brake?