Seems like Scotland is going to go independent, and if Scotland do Wales will only be a matter of time so may as well just can it now?
Elizabeth nor Charles are claiming devine right. They are a unfiying vestige of times past, providing as she did a human constant, an embodiment of the Commonwealth.
So long as their heredity isn't overtly providing them the ability or write or enforce law, it does not seem an affront to democracy.
While Elizabeth has CHOSEN to not use these powers much, any future monarch can. Just look at the U.S. in the last 6 years to see what happens when a country relies more on historical norms rather than law.