Of course not. You were the one who willingly accepted Nintendo's Terms of Service when you used their online services then violated them by hacking the console. GDPR doesn't give you a right to their online services, that's unfair towards Nintendo. Servers cost money to maintain. At best, the GDPR ensures your personal information is protected from Nintendo but they can ban you without using any personal info so if you really thought this would unban you, you should have just bought a second console