Saying that is a slippery slope for kyc means you don't really know how it works.

use case examples:

- sometimes you want to donate to somebody some sats and attach a message but also will be nice to have a "name" attached.

- if you have a service sending back messages through a LN address, is also useful to send a "name" as the sender. Receiver could identify it also and/or use it in a service database. Example: I am subscribing to a service, through their LN Address and attach a "name" to that payment. They can see who send the sats and register me by that filter. But that "name" have nothing to do with my real identity, the service doesn't care about that, just want and "identifier".

- It can be even as a chat over LN. Zeus and Blixt already have a contact list. Could easily attach a LN Address to the contact. Users can chat like that between them, privately, over LN.