That still won't place Harry and Megs any closer to the throne, barring the disastrous deaths of all of William's children. And the odds that she will stay married to Harry for 15 years? Nah.
I think Meghan (and Harry in tow) know they won’t rule the land. But I think they want something “greater” - to be the de facto Royal Couple. Remember when Tony Blair called the late Diana “the People’s Princess”? If they have scores of admirers and psychophants that “outweigh” the REAL Royal Couple, they’d likely be happy....sort of like how Hillary keeps coming back on the scene, how Harry’s late Mother won the hearts of (most of) the Country, and so on. If the youths of today in the U.K. remain supportive of them as they age, they may make it work.