Not that useful as long as One relay didn’t comply 🤔
Discussion
still useful, most relays honor them
they will comply, when they will get "unuseful notes" and unuseful disk space used.
And it is good to have this feature activated now in clients. It will force relay to manage it in time.
If, for a new feature, each (relays/clients) have to wait the other to implement it, no new features would be coded.
It is the decentralize way to code... showing the way.