It absolutely is not a joke. It’s normal for regular name changes to require publishing a notice in the paper as well, the idea being that it’s a way to keep people honest (or at least findable) if someone is changing their name to duck out on their debts. There are exceptions for publishing notices if you’re changing your name due to domestic violence and stuff like that too.
But as is immediately obvious to anyone with a couple of brain cells to rub together, it can be INCREDIBLY DANGEROUS to a trans person to announce in the paper that they’re having a big trans name change!