Not certain how much clearer it can be as I've already quoted the whole conversation to which you asked this question, and it included the words relevant to participate in the privy council. They do not match with the views of someone who is anti the monarchy.
Now whilst I a pro monarchy, although loyal to the Nassau not the Windsors, I also agree that being a member of the privy council should be possible without that constitutional agreement. Or at least access to the information disseminated through that process.
In my opinion, by accepting it as is, he will firstly be hypocritical to his own beliefs, secondly untrue to what he will agree to, and thirdly miss an opportonutity to engage in a discussion for change. As such making it much harder to engage on that in future time, and diluting in the first week his breath of fresh air already.