"Screwing up" implies negligence, but not malicious intent. I think it's likely a bit of both.

They did "screw up", i.e., the financial side of the business thought it was ok to hurt the user experience in order to make more money, and the engineering side was too incompetent to realize the security risk. Why would this level of demonstrated incompetence lead you to believe that they will be better in the future?

The fact that they've gone from minor user-unfriendly features to major violations of trust doesn't speak well to their learning ability or consumer care, however.