If it's true, and I'm not saying it is, then two things come to mind:
Was Team Cambridge deliberately planting stories about Meghan in the media to deflect from Williams antics? If so then, as I said before, it's a despicable thing to do to Meghan, who has really hit the ground running and seems to have a better work ethic than most of the other royals.
Secondly, what would it mean for the future of the royal family if William was proved to be a cheat? I know princes have taken mistresses since the dawn of time but given he's the son of St Diana (whose marital woes were legendary) it would be far more damaging than the events of HM's annus horribilis.