Keep in the larger context in mind:

Your former employer (and anyone else you have done significant business with) can always find some flimsy basis for a lawsuit that will cost you several dozens of sleepless nights and $10k-$20k in lawyers fees, before it is thrown out by the judge.

What is stopping the other guy is they are not pissed off enough to throw $50k-$100k in the toilet for the lawyers fees and distraction to punish you unjustly.

Not signing does not actually protect you from baseless suits, if you run your mouth.