This is the best question nobody has answered yet:
Seriously, core should just increase the blocksize to 2MB in a regular maintenance update. They could even roll this into release candidate v0.12.0. It was never intended to be a consensus rule - only a temporary measure.
Ask Greg Maxwell, he was in this thread for a second.
Is he still part of "core"?
Certainly if he was for it, it would happen.
Ask him why's he's not.