I believe it is unlikely. (Not because I do not believe NSA is hoarding 0-days, but for many other reasons.)
I'm curious: to any professional vulnerability researchers reading this, what do you think?
I used to call everything a conspiracy theory, but then Glenn Greenwald published
"No Place to Hide: Edward Snowden, the NSA and the Surveillance State".
Now i know that reality is worse than the worst conspiracy theorist.
I don't think reasonable people post here much anymore. It's mostly galaxy brained conspiracy theorists and ignormamuses posting political garbage. Reddit-lite on the way to full blown Reddit