The seven virtues provides a useful framework to think about this. Prudence (emotional intelligence) gives rise to justice (knowing what is owed to whom), which gives rise to fortitude (assertiveness), which gives rise to moderation. Moderation without fortitude is cowardice. Fortitude without justice is tyranny. And justice without prudence is injustice. A little esoteric, but St Augustine knew a few things about life :)
It is very evident that [confident jerk] > [lacking confidence]. Kindness and compassion are not substitutes for confidence and assertiveness, as far as both anecdotes and token evidence goes.
As far as society goes, it is removing [confident jerk] in boys. It is not replacing it with [confidence]. It is also not teaching girls to actively value any of your other supposed virtues. Congratulations, most boys are now [lacking confidence], one of the few measuring standards.
Your "useful framework" does not align with the reality of the western world.
1. In my view “confident jerk” == lacking confidence. The confident jerks usually have the lowest self esteem. Their “confidence” tends to be a facade - a lie they tell themselves - which is why they seem to always have something to prove.
2. Assertiveness is not necessarily indicative of confidence. Again, it is clear that some of the most assertive wanna be dominant people are deeply insecure and simply acting out to assuage their internal feelings of low self esteem.
3. Compassion and kindness require true self confidence.
You can be assertive without being a jerk. Society and moral philosophy generally encourage this; and they discourage being a jerk. The difference is that constructive assertiveness is kind and compassionate and comes from a place of confidence. Destructive assertiveness comes from a place of low self esteem (pride/envy). Moral philosophers have written about this for over a thousand years so I don’t think that these values are especially modern.
The writing of St Augustine are a key part of the foundations of modern western (Judeo Christian) moral philosophy. This they offer many insights into moral reasoning in modern western society.
I find this to be a very convenient belief, in the same vein as "criminals are stupid" or "[not my political party] is stupid" or "good things happen to good people" or "bullies are insecure." I don't see any evidence or have any reason to believe that confident jerks are secretly harboring internal conflict, as satisfying as it may be to believe.
I mean the convergence of beliefs across a bunch of religions and moral philosophies is probably pretty good evidence. They were not exactly running randomized controlled trials; but they were smart people who thought a lot about this stuff. I’m not sure that the methods of modern behavioral science are so much more advanced :)
Otherwise this is just like one of those “obvious”, self evident things (i.e. obvious to some not to others). I do concede that there are a subset of jerks who have Dunning Kruger syndrome as well as a small number of true sociopaths out there.
Even the "quit dating assholes" stereotype is obvious, with women falling for the typical cocky jerk who goes against what society claims a man should be. Then it turns out, that guy ended up being problematic and scarred the girl for life.
Does that mean assertiveness has to be dark? No. But frankly, society is doing a lot to kill the "dark assertiveness" while not doing anything to insert "light assertiveness", if you're willing to view it that way. We're not exactly raising boys to be cowboys and gentlemen, we're raising them to be doormats and appeal to women in ways which clearly aren't dropping panties.