That is my question. WTF is Charles Windsor? Doesn't he care a fig for his country, his people and his crowm? And WTF are Harry Windsor and Mrs. Me-Again Windsor. They could register moral indignation, be on the right side of history and take on the tree-hugging king.
The King doesn’t have the power, constitutionally, to dissolve Parliament without prior permission or specific action of of the government.
If a law is not bulldozed in via the Parliament Act, or the Prime Minister asks for permission to call a general election at a really bad time, the monarch retains the Royal Prerogative and in theory can refuse assent. But that’d be like pressing the nuclear button on the monarchy, which is why it has never happened in significant circumstances over the last 150 years. So the monarch is acting no further than as a ceremonial stamp to confirm that government business has been through all necessary levels of scrutiny and oversight.
What the king cannot do is exercise the Prerogative in the absence of any preceding action from the Houses. If government doesn’t propose a bill legitimising or outlawing the gangs, the monarch can’t refuse assent on that bill.
Unlike the Presidency of the USA, our head of state is not an executive branch. The USA can be held hostage by a rogue head of state issuing executive orders while acting unconditionally; the UK can’t.
Margaret Thatcher set the precedent that the Royals have no power here. The Queen made it abundantly clear that the monarchy does not get to even comment on, let alone interfere with, the business of the elected government.