This is a bit different from other #metoo cancellations for this reason. There's no accusations of harassment, just adultery and concomitant deception. I'm torn here between my usual disgust at trial-by-Twitter and also thinking the guy probably needs to face some consequences.
The issue is that the end result is the same.
Trial by twitter, negative impact on the guys career, shattered families, etc.
And all of that before the other party has the opportunity to give their side of the story. If she really cared about his wife/family and them potentially being hurt she has 2 rational options:
A) end it with him immediately and cut all ties.
and/or
B) call or meet his wife to inform her of what's been going on.
Instead she wants to do this in a way that puts
her in the spotlight. Don't get it twisted, she doesn't care about anyone else, she doesn't care about his family, she's doing this so that she can get attention now that she's bored of his dick.
It's disgusting and these people know what they are doing. They are hurt because the relationship didn't (or was never going to) work out and this is their way of lashing out.
The only upside to this is the fact that in the process these women are inadvertently outing themselves. Any sensible guy now knows to stay away.