I wonder if this move is related to this recent story [1] from theappanalyst, which reveals not just a privacy, but also a security nightmare.
The article even seems to mention it "Even though sensitive data is supposed to be masked, some data — like passport numbers and credit card numbers — was leaking."
It just seems to be really fast. The article appeared on HN 21 hours ago. Unfortunately there is no date on the blog post itself.
When I read the report I was hoping that it will have serious consequences for Glassbox and similar services. Good that Apple is taking action so fast. I hope Google kicks in soon too.
There were very similar news that have made to Techcrunch, so this is not anything new. So it cannot be a response to this - Apple has been working on it for some time.
The article even seems to mention it "Even though sensitive data is supposed to be masked, some data — like passport numbers and credit card numbers — was leaking."
[1] https://news.ycombinator.com/item?id=19102036