This is a logical fallacy. That's like saying security of the website is not important because someone can still steal your laptop.

What logical fallacy, exactly? I think you're perhaps misunderstanding the conversation. This translates just fine to your proposed analogy.

In your analogy, the claim would be that some online account is tied to a laptop and whoever possesses the laptop has access to that account. The online service does not permit the account owner to revoke access from that laptop and move the account to a different laptop. I stand by my statement that this would be a serious security hazard. Because yes, laptops can and do get hacked or stolen, just like email addresses.

Where your analogy isn't quite as strong is that at least you can generally add additional anti-theft protections such as full-disk encryption to a laptop, while with an email account generally 2FA is the best you can do.