[est31]

Human brains actually move real stuff around for their computation [1]. Like are like abacusses or some complex clock. Silicon based computers move electrons around which are much smaller and have much less weight. However, you might be right that silicon based computers won't allow further improvements.

So maybe one day we will build computers based on organic chemistry. If they are cheaper and more efficient and work as well as silicon based computers, there is certainly a case to build them.

[1]: https://en.wikipedia.org/wiki/Action_potential