On his own website, hosted on his own server, he has server logs to track whatever he wants, change whatever content he wants to display, and do whatever else he wants.
The only reason to use a URL shortener, is to interpose himself between his server and someone else’s server, meaning to become a third party to the relationship between user and other server.
No, he’s not a third party, he’s the second party in this context because you visit his own website, hosted on his own server.
On his own website, hosted on his own server, he has server logs to track whatever he wants, change whatever content he wants to display, and do whatever else he wants.
The only reason to use a URL shortener, is to interpose himself between his server and someone else’s server, meaning to become a third party to the relationship between user and other server.