In this case it would have been barely possible to do a land landing, but the margin was much larger for a barge landing (since the stage doesn't have to return all the way to the launch site, which takes quite a bit of fuel). In the end it doesn't really matter, though. The cores that land on the barge just take a few days longer to return home.
Droneship landings are particularly convenient for west coast launches, as they can unload them ~20 miles from the factory (which is where they are refurbished, for now at least).
