I wonder how this will all turn out in five years. I think it's becoming more clear that H&M had been thinking/talking/planning on quitting the RF to capitalize on their activist starpower from the very first days of their marriage, if not before.
Removing the right to use their royal titles is not the most important hit against them IMO, They are well enough known to not need the royal prefix. It's that it sends the message that H&M are not a firmly embedded part of the RF anymore. They have voluntarily separated themselves and the RF have effectively closed the door behind them (with a vague olive branch offer to return blah, blah). I think that is what reduces their marketability in the long run.
This has all played out in the public and the narrative has gone the opposite way they wanted. Instead of a bold announcement garnering the sympathy and support of the public for them as victims striking out on their own, it has become clear that they have been seeking great financial opportunities and planning this for a longtime. They didn't discuss this patiently, they blindsided HMQ making foolish assumptions about being able to trade on their royal status.
I do not think this is a MM led action either, I think H has been pushing for this all along too. It's easy to imagine the various PR types who have been telling them how much money their brand is worth, so now it remains to be seen if they get the payday and the international status they want.
I know the media reports rumours and stories from anonymous palace sources all day long and most of it is BS, however I do think the anger of Charles, Phillip and William is very genuine and understandable, they've been painted as cold, hostile, uncaring and racist by the not so subtle hints and well placed news items favourable to H&M. It will be really interesting to watch them all at the Commonwealth event, lots of friendly smiles to be expected but their body language will be interesting!