Author of the article I believe meant the end user was using a crypto-burner SMS verification, such as the ones on this list: https://simplifiedprivacy.com/burners/
Then combined with Tor is fully anonymous. It depends obviously on what you want to achieve
The website clearly lists package forwarding to hide addresses. As VolunTerry points out, it does many sites. And on the MoneroTalk podcast, their team advertised it would do Amazon Concierge service to forward to the person.