Basically the deal is - every time Harry comes over, the risk will be assessed (at our expense) and the appropriate security will be provided (at our expense). But Harry doesn’t want the appropriate level of security. (This is how we know it’s not really about whether or not he would be safe.) He wants super duper security, whether it’s needed or not, because that’s what William gets. William gets it because he is the heir to the throne. Harry’s merely appropriate security is a marker of his relative unimportance, compared to his brother. And he can’t stomach that.
Plus security costs a lot and I think initially he had hopes that if the UK signalled that he needed extra special protection, other countries might be persuaded to follow suit. He’s got no chance of that while the UK risk assesses each visit and only gives him what he needs, which most of the time will be very low key I imagine.
I also think the whole shtick about not being able to bring the children over is absolute nonsense, because the risk would be assessed and appropriate security would be provided. I think he thought losing his security was just Charles / QE2 being petty and punishing him, and that they would capitulate if he threatened never to return or bring the children over. So now he’s talked himself into depriving his children of their extended family and the opportunity to grow up with proper connections to the RF. And still no super duper security on demand. What an absolute imbecile.