That said, the concept is seemingly aimed at blocking ad blockers and preventing browsers like Brave from impersonating Chrome so it can block ads without the need for extensions and such.
The only user-positive use case I can think of for this is for self-hosted software. Maybe it can be used to detect MitM attacks or malware messing with the browser? In practice this will just mean "no Firefox, no Linux, no adblockers".
And no curl, no yt-dlp or youtube-dl, no alternative YouTube frontends, no scraping the web to build an alternative search engine.