I thought this was slightly funny.
Mark Zuckerberg is known these days for wearing t-shirts with Latin phrases on them, especially ones where he compares himself to Julius Caesar.
Bluesky made a shirt in the same style, but theirs says “a world without Caesars” in Latin.
Also most people won’t care anyway. Even big businesses are unlikely to really be that bothered.
For years everyone’s been fine with Twitter and that never had custom domains.
But up until recently, Twitter used the blue checks to verify identity. Bluesky (as far as I know) doesn’t verify anyone’s identity. Instead, your domain name is your verification.