As for your comment about junior engineers, see kennywinker's reply to this thread - I share the same thoughts.
If our goal isn’t to make excuses for the top of the org chart, a more likely explanation is that senior management is heavily incentivizing shipping AI features and this went out as a high-impact change reviewed in a rush, probably by AI.
I’ve been a jr engineer at a large company. I had the power to implement absolutely jack shit on my own. I deeply doubt the security flow for account recovery in meta ai account security was a single jr engineer.
What i think is actually going on is basically a soft form of ai psychosis. Senior engineer gets ai to code ai account recovery feature, that same or a different engineer asks ai to review the feature, and then it gets pushed to prod. Move fast, break things. The ai coded it, the ai reviewed it - the people trusted the ai because it sounds confidently right.
Just like how the ai doesn’t know if you should walk or drive to the car wash, the ai doesn’t understand exploits like this one.
I will agree that anyone that works at Meta is likely not somebody who values privacy very much, though.