Here's my opinion.

"Apprentice is Barred from this AI race" is the phrase.

"You (OpenAI) Apprentice are Barred from this AI race, because, well you are just apprentice"

"Because you are still an apprentice, you (OpenAI) are prohibited from participating in this AI race."

To be clear, that is not my personal opinion of OpenAI, I believe OpenAI brought so much innovation to this LLM space.

Just sharing what came into my head, why Google picked that name.

To counter Sun Microsystems' dominance in the Java market, IBM named its IDE as "Eclipse."( blocking Sun).