Sadly I think the problem H&M have is they are very "marmite" celebrities.
When they behave poorly their "team" make excuses for them and when they do something arguably good the vast majority of the public view this through the lens of a couple prepared to sell out their own families for $$$ which is far from being kind and look for which "angle" they playing for on this occasion (even if there wasn't one).
H&M are a pretty textbook case of how to self immolate your own public image.
One thing we won't know is just how many causes they have sought to support only to be told "no thanks" because whilst they might bring publicity, they also "taint" the event/charity by virtue of the chatter generated being about their hypocrisy rather than the charitable work.
They could have done so much good, yet they just went hell for leather in making multiple allegations (aka their truth) of which many have been disproven or they have backed away from.
They've played their biggest card re: the royal racist and that didn't do the damage I think they thought it would.
Personally I think they are in deep shit. They've sold the family silver and are starting to realise that they've burnt their bridges in maintaining a connection to the only thing they can monetise - Harry's family.