Yes, you can cut off the name, but your peer will see your name again after joining. So, you should preferably pick a name that is not compromising for you in the first place when creating a throw away profile for invitations.
Shortening the invite link would defeat the whole purpose of providing cryptographic material out of band.
Centralized usernames would defeat the purpose of the decentralized nature of DC, open up a centralized actor to metadata collection and could MITM and deny people making connections.