The twerking video release was to attract big attention - nothing more, nothing less. It wasn’t “sharing a lovely, fun moment” - no way. Meredith Maines along with Meghan knew that it would cause a stir and boost M’s followers - which it did - job done.
It’s an interesting compare and contrast. Meghan’s video garnered some 47m views on instagram. Meanwhile, the Wimbledon instagram account posted on their feed a video of Kate entering Centre Court for the Women’s Final and being applauded by the crowds. It garnered 26.3m views and was by a long way the most-watched video of the entire tournament (the next most-watched - the two champions dancing at the ball - had 14.8m views)
So one video deliberately intended to be eye catching and newsworthy, and well promoted (Meghan specifically talked about it on her next podcast etc) did its job very well. I’m sure Meghan and her team were rightfully delighted by that.
However, another video of an unplanned, spontaneous moment - just the woman in question doing her job - also did incredibly well at getting attention (when posted by a third party, too, not even Kensington Palace) even when not promoted at all. It’s hard to compete with the latter.