This terminology can be confusing for those who aren't into IT. Here are a few paragraphs from the article that provide a little more clarity:
"The Chinese government has deployed an update to its national censorship tool, known as the Great Firewall (GFW), to block encrypted HTTPS connections that are being set up using modern, interception-proof protocols and technologies.
The ban has been in place for at least a week, since the end of July, according to a joint report published this week by three organizations tracking Chinese censorship -- iYouPort, the University of Maryland, and the Great Firewall Report. Through the new GFW update, Chinese officials are only targeting HTTPS traffic that is being set up with new technologies like TLS 1.3 and ESNI (Encrypted Server Name Indication). Other HTTPS traffic is still allowed through the Great Firewall, if it uses older versions of the same protocols -- such as TLS 1.1 or 1.2, or SNI (Server Name Indication)."