There is zero evidence that keeping the name of a 6mo baby is in his best interest. None at all. It's an ideology that about not upsetting the feeling of the birth family and keeping up the power of SW.
That's not to say that any one adoptee might well say that they didn't like the change. But they plural of anecdote isn't data.
There's zero evidence that identity is all about name. You might as well say " well his birth family are all alcoholics so that's part of his identity we should keep ". If they have all been problem drinkers for generations, isn't that more important that a word on a six month old legal document that baby has never seen and soon will be superseded?
If changing names is so damaging why do so many women chose to do it as adults ? And don't say " oh that's last names so it doesn't count". And every adoptee has their last name changed and no one even questions this ( because it's in the law) .
Many adults and children choose the form of their name " I was born Catherine but I always use Kate now " and none of them seem to be traumatised.
If the baby is called Jedi -Warrior and you change it to John , why would one name ( which no ones know or calls him ) be " his identity " and the other not ? On the contrary, it's a burden to have a name that doesn't fit in with others in your group. You are Always marked out as different and an outsider.
I'm sure it would be the same if John was in a family / class / workplace with Darth, 8D8, Wedge and Yoda.
I'd say nothing to SW. Call baby by pet names such as sweetie, precious etc, whatever you called your first child.
Submit the adoption petition with the name " John Jedi - Warrior Smith" .
Then he can be John Smith, John J smith or J Jedi-Warrior Smith etc as he chooses.
As a PP said, if you call him by his middle names then Schools and doctors etc will get confused. Give the name you choose first.