It's as if someone created one element that is perfectly suited to build microelectronics. Sure, there are other materials that improve on one property or the other, but there is not a single other element which balances properties as well as silicon.

Not even mentioned yet: - Excellent mechanical properties of the single crystal (think MEMS, or wafers that don't break all the time) - Piezoresistive properties can be used to measure strain (also quite unique due to silicon band structure) - Optical properties perfectly suited to detect visible light (think detectors, image sensors). Good combination of band gap and carrier lifetime to build solar cells.