If the polo thing has already been shot, then I don’t think Harry will appear in it much other than through archive footage. “Long the bastion of royalty and the elite <cut to shot of Charles as a young man playing polo, couple of Saudi princes, and neat segue to Harry on a horse in his 20s>, this glamorous and exclusive sport is actually a clash of highly trained athletes and their beloved partners, the ponies”. As a discipline and a scene, it does have it all: it is rigorous, it is exclusive, man and beast, glamour, glossy women being feminine. Trouble is, Harry only accessed the world because of who he is (he’s not known as one of the better player - none of the royals are, unlike Zara and her mum with show jumping for example). Who knows if he actually enjoys it, he may just have been forced to do it. Still, he has decades of experience, and he can actually do it. Meghan has been there for two minutes because she married a player, dipped her toe in, saw the social exclusivity and $$$$ expenses of the sport and thought “well, I’m a duchess married to a prince, this is rightfully my world too now and I’m entitled to use it as my own [to fulfil my contractual obligations]”. Never mind that she famously banned him from hunting and made him sell off his Purdey guns gifted to him by his grandfather.
There’s no getting away from the fact that neither of them put in the hard graft to credibly lecture others about, well, anything. They’re dilittantes at absolutely everything except for (1) being Prince Harry (2) hustling as an actress in LA. That’s literally all they have authority to speak on. It’s all desperate, selling whatever scraps of themselves remain. Fancy making tv shows about your part-time hobby and bring a housewife, and expecting people to think anything than that you’re complete tools.