The ending bits that imply a darker vision of this future suggests a very different direction for the show. Still, there are Star Trek episodes that do consider the holodeck from this angle. Maybe we need a mirror universe holodeck episode.
I expect that the Very Short Treks won’t be entirely non-canon. For instance, some episode might introduce an event, place, or technology that is actually canon even if the events of the episode itself are not canon.
Alternatively, they could be loosely canon in the same way as the Lego Star Wars shows/games, with the rough events and plots being canon even if exact details are not.