Yup! It is "Look what nasty people my family are, they don't care if my family are attacked and injured, they don't want to meet my little daughter, and they won't even let me pay for our security against that happening." Manipulation of the perception by the public of how the RF is treating Harry, Meghan and their family.
Good points in this video.
The Met police force security is for large-scale public order, they only provide paid security for events where a lot of the public need to be protected. They are not for hire by any well-heeled celebrity or foreign magnate who is visiting this country.
When there is a request for their services at a large event, they assess the need and take a decision without consulting the Palace
Non-working members of the RF only have police protection when they are on official engagements - and Harry has opted out of those.
There are many private security firms which he could hire to do the same as the Met would.
Plus - if he is here to see the Queen on her Jubilee, he will have the benefit of being on the fringe of the Royal Security agents who are protecting her
If you ask me, the truth is that he and his family have been out of the limelight for a while, and they feel it is time to appear in the tabloid headlines again. What better than to latch onto the Royal Jubilee and make sure that they get in on that act with some poor-me publicity? - while simultaneously giving the RF some bad marketing by making them appear mean and spiteful?
