Even Charles, with his support of some environmental issues, is in no sense a social reformer, as his stewardship of the Duchy of Cornwall has shown in his time as heir apparent.
It blatantly tinkers behind the scenes, in line with its current constitutional rights, with legislation that may affect its many vast landholdings and financial interests - such legislation has to be run by the king before it even proceeds, never mind the final process of royal assent. On other issues, it goes with the flow, with only token disapproval, if any at all.
There have been no grumblings or even comments from Charles or the rest of the royals at the extreme actions and statements of the most rightwing government this country has ever seen, so the idea that the royals represent in any way a "voice for the people" is utterly laughable.
For instance, Charles has said nothing about the sinister arrests of protesters before and at his coronation, for only a few of which the police have now started offering cheap token apologies. If there was a time when Charles might have called for mercy and indulgence, not to mention decency and common sense, from his position of extreme privilege, this would be it, and it would set a better tone for the start of his period as monarch by upholding freedom of speech and peaceful dissent. Instead, silence as the dust and glitter settle on the spectacle of his extravagant concert at Windsor Castle.
What the royal family does do is add a veneer of distraction to the government's agenda of the day. That's the illusion of "balance" you mentioned. It's anything but.
The royals' obscene wealth and entitled isolation from the real world most of us inhabit are in stark contrast to the tightening of belts and increasingly draconian laws the rest of the country are expected to bear, and it's a deeply conservatizing force.