Apparently, when the mega ultra super trillionwhatever dollar spy company Google reads metadata for a Twitter profile, it just grabs the first one on the page. So if a Twitter profile does not contain a description, the first one to show up (probably X, from a "user followed X" notice) gets published underneith the linked profile.

This can give pretty weird results. And I'm perfectly happy to have weird federation bugs when a company like Google can't even handle public profile metadata collection properly.