For less ideologically-committed companies than P&G, the following approach has usually worked to stop a misandrist advert:
https://old.reddit.com/r/MensRights/comments/4e876e/how_to_affect_misandrist_adverts/

However, while such arguments may be useful, P&G is too committed ideologically for a reasoned approach alone (to Marketing) to work.

So, here's another idea:

https://www.bloomberg.com/news/articles/2019-01-23/p-g-blames-beards-for-grooming-unit-lag-but-sees-hope-from-ad

Organic sales in that unit fell 3 percent, a trend Chief Financial Officer Jon Moeller said can be traced to fewer clean shaves.

Alternately stated, at best, the advert wasted shareholder monies and failed to stem sales decline.

In a competently-run public firm, that would be grounds for dismissals - of the marketing agent Kim Gehrig, of the marketing staff, of the designers of the SJW marketing strategy, including the P&G CEO.

A number of MRAs holding 1 share, proxied to a single rep, might attempt to raise the dismissal issue at the next shareholder meeting.