I don't think that diversity is over praised. I do think that competence too often takes a back seat to the "it" popularity factor.

People become popular for being attractive and likeable, not for being competent problem solvers. If Abraham Lincoln were alive today, it's unlikely he would be able to attain the White House. I'm sure Brits could easily think of a Prime Minister prior to the advent of Television for whom the same is true. If Donald Trump had not spent so much time building name recognition on TV and buying cameos in movies (Especially family movies like Home Alone 2), he never would have gotten elected. Same for Boris Johnson. He spent a lot of time and a lot of years seeking out the camera and working that hair flip.

We tolerate a lot of roguish and knavish behavior from politicians playing "characters". We give them power they don't deserve and really aren't suited for.