Part of maturity is learning delayed gratification. A child wants what it wants right now and if it doesn't get it, it throws a tantrum demanding it. A mature adult sees a long term goal and sets plans in motion to attain that goal.
Maybe Harry and Meghan did have very valid reasons why they couldn't remain as senior working royals. Maybe they were "victimized" and maybe they weren't. Its all perspective. As adults, they chose the means and the methods that felt right for them to pursue what they perceived a happy and fruitful life would be. With the methods they chose, it solved the problem *then and there* but what they didn't plan on was repercussions from their actions that would affect their future such as the "paycheck" from the "Bank of Dad" that floated their working royal roles would dissipate.
The press against Meghan was a constant and, I believe, had a lot to do with contention within the family. Where was the support against the mean old press? They left. A year later, there isn't that much really being reported on Harry and Meghan anymore in the press. They're not making front pages. They're seeing the "institution" go on like clockwork even amid a pandemic. The world didn't stop because Harry and Meghan left and in the US press, there were far more other things to make the front pages here. Royalty isn't a big deal in the scheme of American life. If they planned on who they were to open doors for them, I'd not be surprised if over the past year, they found that wasn't the case. The Duchess of Sussex ranks right up there with Queen Latifah, Prince and the King of Rock n' Roll.
Perhaps the interview was a cry to be relevant again as they once were. They were admired, applauded, cheered and perhaps even loved. What they didn't realize is that it was the global platform of the monarchy and the institution itself that put them into the position of being acclaimed. Now they're going to have to earn what they have not only in terms of money but also respect and admiration for who they are as individuals. They got what they wanted. Now it seems like they don't know what to do with it.