Most clients will show some kind of 'verified' badge if you have NIP-05 name, so you look more trustworthy. And when someone mentions you they won't have to specify your pubkey, but can just type your NIP-05 name which is easier to remember, and then when a post with your mention is displayed, your NIP-05 name will be displayed, not pubkey, which is again - easier to understand and remember for other people.