[VBprogrammer]

I'm almost certain that the solution in this case will be training. Almost exactly as you've said in another comment. The correct response to an commanded stabiliser movement is to set the stab trim switch to cutoff. Pilots will probably experience this failure mode in their next recurrent training.

The accident is more than likely to be attributed to a system being added without sufficient guidance being added to the PoH, some degree of maintenance failing on behalf of the airline and finally a failure of the pilots to identify an issue and take appropriate action.

It's unlikely that those particular holes in the cheese will line up again in the near term given the emergency AD. No reason to ground the fleet.

[WalterBright]

That does seem likely, but very often the eventual cause discovered by the NTSB was not what people initially thought it was.

It's still worthwhile to warn the pilots about uncommanded movement and reiterate what to do about it. At this point I doubt any 737 pilot doesn't know about this.

To add to your summation, I'd expect the mechanism's inability to detect a faulty angle-of-attack sensor needs addressing.