I've said before that I think H&M both lack the ability to make long term strategic plans.
As a couple their behaviours are very reactionary and have been right from off with Harry's unprecedented press release when they were dating.
The megxit half in/half out was after H was told to wait and come back with a proposal. Post being told no, they then changed the narrative to how they "had" to leave due to a toxic family and UK press.
They "had" to do Oprah and the book/Netflix as Charles cut them off (evidence shows otherwise).
There's no evidence at all they ever paused to consider the long term outcomes.
There is one person in all of this they were unwise to piss off. They though is was The Queen.
But anyone with an eye to the future would have realised the most important person to keep on side was William, because if you play a long game he's the one that really matters. Whatever Charles may do William can undo.
Will William ever welcome them back?
I think for M not a snowball's chance in hell (not that she would want to come back anyway) but I very much doubt he would open his arms again to H.
Maybe he's more forgiving than I would be, but the betrayal by the only person who really understood what you had lived through and who you felt would always have your back must have been profound.
The repeated "stabs" to him and Catherine (remember her being described as a sister to H) demonstrate an utter disregard for those relationships. This wasn't a one off comment but drip feeds of anecdotes and information through Scobie, Spare and their interviews.
Who would welcome that back into their life? Their children's life? To set that as forgivable behaviour?
Truth is W doesn't need H as much as the reverse.
There might forever be a "hole" left but W has got a lot of loyal people around him to fill it, something H is sorely lacking.