This is a mix of a witch-hunt against Musk and political maneuver as Breton is said to be eyeing the job of President of EU Commission in next year's EU elections.
Not actually a witch hunt, as explained in the letter it’s in response to the new DSA laws which they have been told would be enforced for a long time coming now.
Of course it can be both... It would be naive to think this is all perfectly neutral and that there is no game being played, as per my previous comment.