If a law is passed by the House of Commons it's classified as legitimate. As far as the monarch of the day is concerned he or she is supposed to be above politics, above getting their hands dirty if you will. That's the main justification for having them.
I think what you say above reflects a very common misunderstanding, which even educated people repeat as if it's gospel. I believe you are mistaken. In fact, the Queen is supposed to be impartial, but that does not mean she is supposed to be neutral. Her role is political and she can, if she wishes, intervene in politics. There is even an argument that it is her duty to do so, and one of the popular criticisms of her is her failure to do so. In any event, it's fundamental to her role to do so, though I would completely accept that she should be extremely circumspect and cautious in doing so, and it probably should be rare.
Ironically, Elizabeth II is perhaps the most political of all the late modern monarchs. Consider for instance the Queen's Annual Christmas Message. What she says is extremely political and ideological. That brings us to what disappoints me about Her Majesty and why I believe she is one of the worst monarchs in this country's history. It is not the fact she intervenes that bothers me, it is what she says. If you search on YouTube or through some other source one of her early televised Xmas addresses from the 1950s, you will notice that she is a happy young woman, and her message is traditional and positive, and she has a certain warmth and charm about her. Now, in her old age, her messages have become patronising, preachy and ideological, in tune with the toxic orthodoxy of the time. I think part of her problem is her brand of Christianity: Calvinism. It can be easily twisted into a self-abnegating mindset.
She did not stand against the times. She should have been steadfast in 1997, instead she relented and then gave away more and more, thinking this would save the Windsor dynasty and/or the Monarchy. I think this was wrong. She should have got her hands dirty, but for the opposite side. Better still, she could have simply maintained a studied silence in the face of it all - that would have sent a powerful message too.
I don't personally believe in mass democracy. I think people voting on things is dumb. Liberty is the system I prefer, though that is a misnomer because it is not really a 'system'. It is more of a philosophy that depends on each person practicing the same broad value of leaving other people alone, with interference only to the extent needed. I think in that way of life, most problems would sort out themselves, mainly through voluntary decisions and choices.
Law should be for the courts, not Parliament. Parliament should only intervene in society in very extreme circumstances, such as national territorial defence or a genuinely lethal pandemic that has scores of healthy people dropping dead in the streets, etc.
