Not really. The difficulty of invalidating the patent isn't the real barrier to standing up to these sorts of legal threats. The real barrier is that
whether you win or not, it costs $100,000 or more to be sued in a patent lawsuit.
Here are your choices:
(A) Pay up. The extorting patentholder charges you $80,000.
(B) Hire a lawyer to defend you in court. The lawyer charges you $100,000. You also might lose and have to pay damages.
(C) Defend yourself in court without a specialist patent lawyer. Unless you ARE a specialist patent lawyer, you are guaranteed to lose. Pay triple damages plus lawyer fees -- actually, just pay everything you own and go live on the street.
Which would you choose?