What is unfair about wanting them to either lose their titles or not have security or not be funded by Charles? Those are not extreme - they are consequences for their actions...
I think it's extreme to ask for a removal of their titles. Thus far, no prince ever lost his title. Not a king who abdicated and took his whole Duke of Cornwall/Lancaster-money with him, no prince who was killed as a traitor by his close relative the king, no one! And now Harry should loose his title because he wants to live half of the year not in the Uk? Just think of it as doing nothing half of the year for queen and country and you end up in the position of the son or daughter of a second child of a monarch...
That only can happen to Harry once the queen or later Charles declares his will that all children but his and the next monarch's first are no longer HRH. Like it happened in Norway. But that was, before Sverre was born.
It is as it is and it will be as it will be according to the wishes of the queen and the PoW. And both have no interest in shaking the rank of their own family. And what if Harry looses the HRH? He will be His Grace, the Duke of Sussex and everyone will use that title if they had used the HRH before. And no parliament will strip a Royal Duke of his peerage if the queen will want him to keep it! Because this would degrate the value of such Royal titles, make them into something worth nothing.
From what I gather with Prince Andrew, I guess that the political question of how much the government is willing to pay for security for Royals has been decided and they will be stricter now than they were with Royals who don't work. Now it's Andrew but they will come for Harry and Meghan and that's okay IMHO, for as soon as the police has convincing information that something is actually planned against them, they'll get their security back.
Not being funded by Charles is unfair as long as they don't have regular jobs and if they work for their foundation, they should be payed for out of the foundation's money, as is usus for people who are not doing it volountarily but need to earn their money by working. A relative of mine is working for the Red Cross professionally and guess what: he gets payed for it. So either Charles pays for them so they can do charitable things for free or they work for their foundation and get money from there or they need to work on the free market doing whatever is offered and they can do (and if that is not okay with the RF, they have to support them). They don't seem to need too much luxury (Frogmore Cottage is much smaller than the housing of the other Royals) and in Canada they could have another countryhouse payable by their own money.
So I think your "consequences" would mainly mean to change the Royal system of the UK because of Harry and endanger it with that, so I doubt that the queen or Charles will do that. Police will recommend what is necessary and the government will decide what is payable and find a solution and if something happens, they'll find somebody responsible. If not, all was well decided. And for Charles to support them: someone has to! Either Charles or the foundation or an employer (if the queen and Charles allows that, because now that would be quite bad potentially!)
What bothers me is that Meghan, who is US-American (even though she is the granddaughter-in-law of the Canadian Head of State) just goes to a Canadian charity with political aims and supports them. I think that's a bad way to treat the Canadian's hospitality when in her home country other charities await her to support indigenous women... I mean, I find the treatment we can read about of these native Canadian women wrong in a lot of aspects and there should be help but as an UScitizen with the aim to becom British, she should not become politically active there.
When I think what they could do with charity that they wouldnt be allowed by the Royals, I only come up with things that they shouldn't do as foreigners in Canada or Royals in Britain. They could use their foundation eg as working Royals eg to help British (or USAmerican) women with offers of support, education etc, just like they already did, so where the beef?
Or they could go "on holiday" for some month to the Caribbean or Canada and get therapy/psychological help to cope with life in the Uk. Then work there in fields okay with Charles and take the next pause when needed, but stay away from the papers.
What Meghan has just started to do in Canada is going to create even more and negative waves, IMHO and I'm afraid of the results.