If pretending to delete data is typical for the industry, then we can't know for sure unless a company is breached or an employee leaks the info. It would be very easy to sue a company for lying about that.

You may be right that many companies behave this way, but they at least pretend that they don't. The companies I've worked for have always been extremely conscientious about honoring data-related terms, even if no user would ever know. The fear of getting sued is strong.

Probably not: most of these companies have user agreements drafted by actual lawyers, and those agreements are binding.

In any case: when I say that Avid Life is nowhere near the bottom quartile for companies when it comes to security, you can take that to the bank. Or, don't, if you're worried about taking things to places that won't lose your data in a breach. I guess you can take your data to Facebook in that case.

Snapchat didn't even delete the pictures, to start with. They just made them unavailable to the interface. Which is similar, and maybe enough.

Given backups and billing records and stored message histories and so on, its not really a question of 'deleting an account'. More like 'making an account no longer visible/available to the current interface'. Nobody thought they'd wipe any disks or anything, in anticipation of a big data breach, right?

This is important. The only reason this is much of a story at all is that the "affair" angle makes for very marketable stories. Otherwise this is strictly dog bites man.