I mean, 2 they couldn't really do anything about because that's how the story works.
I'd like to think WB were prepared for 3 because that seems like the obvious impact from having them available to watch on DC Universe, so the incentive for more DCU subscribers and streaming numbers would offset the impact on physical sales.
I wonder if Death/Reign had anything to do with it. I believe the animated movie team produce stuff well in advance, like several years in advance, so I'm not sure if they would have been aware of sales while producing the 2020 slate.