It's worth it but it bankrupts you.
No customers, no investors, and all your cash gone before your appeal is heard.
Block all EU traffic. Just cut the transatlantic cables.
I don't think there's a need to cut the transatlantic cables, but if a company doesn't want to take proper care of user data then it's perfectly reasonable that they stay away from that market and let other companies have that business.
But you are supporting the argument that you could be illegally (according to article 83) fined 4 million euros as a first offence because a regulator wants to be disproportionate and set an example with your small company and then have costs of 10-100k to throw out an obvious case, but it wouldn't be worth it?