King Charles tells Britain to weather the cost of living crisis whilst wearing a hat worth 5 billion pounds.
(thespectaclemag.substack.com)
To be fair, the crown's only "worth" is as a collectable.
It's not equivalent to, say, 750,000,000 kg of Nutella. E.g £5 billion of Nutella. You can't just sell it and distribute the Nutella, it has to be manufactured for £billions worth of work.
The crown has no utility. Its gems don't do anything productive, relative to their value. It can't pay engineers and farmers and such wages to make Nutella, because what are they gonna do with 1/10,000th of a crown?
Practically, if the UK govt sold all royal stuff, what would happen is some ultra-rich would buy it, and... sit on it, at the expense of other collectables they'd have bought instead. That doesn't improve much.