The heading is somewhat misleading, in that one might read it as "the troll lost all rights to any patents, ever." If you (correctly) didn't read it that way, you can ignore the rest of this.

What they actually lost is that patent. It was reexamined and all its claims were cancelled. Reexamination is a standard tactic against a patent infringement suit, and we did it all the time at Google. A reexamination is a mini-trial, with no jury; just a bunch of patent law experts. It costs less than a full trial but still can be $500,000 or so.

A troll will offer to settle for a small amount rather than risk getting their patent cancelled. I think it's fair to call it "irresponsible" if you pay them that ransom, but of course, it's cheaper for you that way.