As the OP of the /r/linux thread... What inspired the thread is that I bought an SD card and while on the dev build of chromeOS I was unable to use it with ext4. I distinctly remembered it being listed as supported at one point a year or so ago and then I ran upon this thread: http://www.reddit.com/r/chromeos/comments/2iuix3/trying_to_i...
So I made a thread on /r/linux and it absolutely exploded. I made it figuring that a number of users would click through and post that this was a stupid change and hopefully get the decision reverted. They claimed there was no userbase for such a feature and I knew exactly where to find one. That said, it blew up way more than I was expecting.