This isn’t just conjecture — it’s also been confirmed by research.
You have referenced one study, by one female professor and that's all the proof we need to debunk a first hand learned lifetime of knowledge ? Not convinced.
To begin with, the meme is that women are more willing to express things verbally. Certainly women are much more willing to discuss matters with other women and even men whether they want to hear it or not. Men typically work from the inside out relying on themselves to make certain conclusions about their priorities. Women, on the other hand, tend to make conclusions about priorities by finding consensus with others. This is seen as gossip and gossip has a bad name. And we all know women are very quick to trash other women just because.
Woman express themselves more openly which is interpreted as "drama". One of the biggest complaints woman have about men is that men don't express themselves openly about what's bothering them. The second major complaint women have about men is they aren't emotional. Men aren't particularly good at drama because feeling are less important to them than physical things like cars, sports and other things men like to look at. Men are less likely to trash other men because they don't want to get punched in the face. You know "them is fighting words". Words have consequences in a male setting.
Sure men are more likely to get into physical altercations and yes, start wars but that has nothing to do with backbiting and defamatory language. That's another topic we could explore.