I personally do not follow or enforce the name rule.
I have never seen that rule played by the book, in any of the Dungeon World games that I have run or played, and I have never seen negative consequences as a result of that decision.
The official Dungeon World game sheets have a blank box for name, with a list of possible names below them, this seems to express an intention that it is acceptable to choose your own name, even if the rules do not say it explicitly. Is different of the "Look" attributes, where it seems that the intention was to choose one. (That changed in version 2.0 of the playbooks, where Look Now also has blank lines for you to write your own option for each option, but those blank lines are in line with the other options, which to me still indicates a more solid suggestion that people choose one of the options provided instead of a brief.)
Having said that, choosing the names on the list has several merits
While looking for this answer, I found arguments from people who do Follow the rule of the name, and swear by it. For example, this forum thread that addresses the same problem in Apocalypse World, (linked to this question related to the answer) has more details.
In one word:
- The analysis-paralysis is broken, which is important when the characters are created at the table (which is the norm for Dungeon World).
- Help players "share" their characters. If a character is completely formed in a player's head to the point where they can not even bear to change the name of one they chose, that character was possibly not created in the cooperative spirit that Dungeon World expects.
- Guarantees that all names will conform to the same configuration. All magicians will sound magical, and all Elves will sound Elf-y.
- It provides restrictions for creativity – all lists do. The player is asked to create a character within the options offered in the playbook, instead of being given a blank canvas.
- If players find that the name lists are too restrictive, they can talk to their desk about how to make an exception to the name rule, so a conversation is started about how to make exceptions to everyone the limitations of playbooks and how much the group wants to bend the rules.