This is a bit like saying "I didn't know passeordstealer.baddies.com was a phishing site when I typed in the company's password for the bank, so it's not my fault all our money was stolen!"

For sure he is the victim of an adversarial attack against him and Nvidia, but as the leader of one of the most valuable companies in the world in am industry where IP and company secrets hold huge economic value, then you really need to expect and anticipate that spies will be trying to infiltrate your org and steal your secrets. I think you can clearly say he has demonstrated bad judgement here.

Him being removed for sleeping with a spy would not necessarily be intended as a punishment for sleeping with her, it's a self defense mechanism to prevent the spy from continuing to have access to a highly placed, compromised individual