So the more identical the committee members are, the smarter the committee?

At least a committee of 10 identical members wont be dumber than a single member most of the time. A committee of clones is just scaling up compute in order to solve larger problems. Imagine if you could clone yourself with your knowledge and mental state, much more useful than trying to cooperate with another human.

According to Condorcet's jury theorem, a committee of 10 identical members may be smarter than a single member.

This seems obvious to me, as there'd be ten times more computational resources.

No, it is because the probability of arriving to a correct answer increases when there are more members in the group, but only when the individual probability to arrive to a correct conclusion is higher than 50%. Group of smart people is smarter than an individual. The opposite is true too. If the individual probability is less than 50% then the group of people is dumber than the individual.

The answer must also be within all of their domains of expertise for the 50% to have any meaning. You can’t have a “room full of smart people” as you’ll just arrive at suboptimal outcomes because your consensus relies on the lowest common denominator of understanding, which between experts in differing fields can be pretty low.

In the context of Condorcet's jury theorem, the percentages refer to the chance of voting for the correct outcome. Think of a legal trial and there is no ambiguity about the meaning of "50%" is.

I always felt that the decrease in intelligence is a side effect of the necessary consensus mechanisms.

10 genius clones would still take on various roles/positions in the system, requiring some optimization with respect to alignment under time/energy constraints.

But the committee-thinking is still constrained by the language. Any committee-thoughts must be coarser and slower than the member thoughts.

We're trading depth for breadth, or something like that.