While I share your outrage over this change, I guarantee that those making these decisions are not so stupid as to "automatically believe" anything. Their belief, whatever it is, would be based on studies and information, not an "automatic" setting or default view. And I would be extraordinarily surprised if they believed this policy would have zero impact on bookings. People in management at big companies are smarter than your average 6 year old.They automatically assume the guest level bookings will stay the same and that this would not impact it.
They may well have underestimated the effect it will have, but it won't have been due to an "automatic" belief or one that doesn't consider basic microeconomics.