I think Netflix would have been happy to continue the way things were but unfortunately Netflix users only have themselves to blame for abusing password sharing where it reached a point where it was out of control. Reddit, Facebook, Instagram and other social media platforms that allow communities to converse with one another all have posts where people have spoken about letting their friends, school, college and uni buddies, work collegues have their Netflix password. Some have mentioned about letting family members in other countries have the password. I have no doubt there are thousands upon thousands of college and uni students who have been given a netfilx password from a source not related to them and then it gets passed from friend to friend to friend.
You cannot blame Netflix for bringing in tighter controls on password sharing.