I just reached 10k on SO yesterday. Today, when I was going to inspect a spam question, I saw this:
I expected that it should be hidden, presenting me with a link to the revision history, but it wasn't. I'm not a diamond mod, so that's too explicit to show me the content directly.
I switched to desktop view, and saw the question hidden as expected:
However, spam and rude/abusive answers are properly hidden on mobile web:
This well indicates that a similar issue occurred when masking was first done for answers. Masking for questions wasn't implemented on the full site until later, so it appears to be a very similar case. Also, it's the only other result if you search for