@trwnh fun fact, webfinger actually supports URLs and [in theory] phone numbers!
The key (and this is a social science and cultural insight, not technical) is that when you ask someone's "name" or "address" they need something that's unambiguous, personal, and opaque in the sense that it works everywhere (online / distributed, it needs to be globally unique, too) or they won't use it.
Bare domains aren't ideal because (1) they're expensive and (2) management is hard.
@blaine tumblr made it work so idk if it's "ideal" per se but they definitely had a cultural thing going for quite a while with "dot tumblr dot com" even being a meme at some point
it can't be too hard to manage tbh, the modern version of this is atproto handle services that do nothing but allocate you a subdomain for use on bluesky