I wish I could say I was surprised, but Facebook celebrates a mindset of “go fast and break things” in development, so I am not. The DNA is programmed to reward recklessness and poo-poo security as an afterthought.
My opinion is not based on intimate knowledge of the developers, but on the API’s that I have had to deal with, the way they make radical changes to things like the Marketing API on the drop of a hat, and through their partners into a scramble to keep their apps up to date. Much worse than Google.