No, it would disarm the group whose software is used by everyone else. If you're a small company, it's not likely that you have written stuff that Facebook uses. So, that world looks like one where all big companies are untouchable, but they can easily pick on small companies. Really not good.
Nope. See other replies. The license termination clause only goes into effect if you as the user of the software are the initial aggressor in a patent suit.