where the committee perform worse because the “forced” member

Ah, the common strawman. A committee where everyone thinks pretty much the same is somehow better than one where a few have a different opinion?

Sometime yes, sometime not.

It all depend on the context. The direction of a project ? Then maybe the fact that the committee has at least roughly the same vision is a good thing, it keep the project focused and progressing, as long as there is a way to offer suggestions.

A political group ? Then it is better to have more points of view, as long as you can decide something in the end.

There is not a single best solution.

Such discussions took place decades ago when pretty much every manager was only male. And they often honestly thought they did the right thing. When there were more women forced to be managers the group as a whole got better insights into different opinions. Which helped to see that certain things could be done a different way.

That to me is history, plus rather logical.

On the other hand I can point to examples where when a woman, to stay within your example, were put in charge the result were disastrous, so what ?
Maybe if we start to think that being in some groups does not inherently make you a better candidate to something than we will start to solve the problem.

Having a few people with different opinions is further usually good for a committee.

As long as they know what they are talking about yes, else it is just stupid.
The point of all this discussion is that Jon Ringer objected to have an hard requirement for one person in the committee need to be from a minority, which honestly is not that stupid thing to say.