Has quantum mechanics really been successfully applied to engineering technology?

Quantum mechanics has been successfully applied to engineering technology. The microscopic world must be described by quantum mechanics, and the properties of macroscopic matter are determined by its microstructure. Therefore, quantum mechanics must be used not only when studying microscopic objects such as atoms, molecules and lasers, but also when studying the properties of macroscopic substances such as electrical conductivity, thermal conductivity, hardness, crystal structure and phase transition. For example, why don't electrons in hydrogen atoms fall on the nucleus? Why do two hydrogen atoms converge into hydrogen molecules? Why can carbon atoms be combined into graphite, diamond, soccer olefin, carbon nanotubes and graphene? Why does salt NaCl form ionic crystals? Why are some substances very stable and some substances prone to chemical reactions? Why can copper conduct electricity, plastics do not conduct electricity, and silicon is a semiconductor, and many substances become superconductors at low temperatures? Why is water frozen below 0℃, liquid between 0- 100℃ and vaporized above 100℃? Why can we make all kinds of special steels by changing the composition of steel? Why can lasers and light-emitting diodes emit light? Why can chemists synthesize many new substances more than the original substances in nature? Why can we know the elemental composition of distant planets by observing the spectral lines in the universe? ..... The fruitful scientific and technological achievements in modern society are almost all related to quantum mechanics. When you turn on an electrical appliance, the conductivity is explained by quantum mechanics, and the working principles of power supply, chip, memory and display are all based on quantum mechanics. Walking into a room, the properties of steel, cement, glass, plastic, fiber and rubber are all determined by quantum mechanics. When boarding an airplane, a ship or a car, the combustion process of fuel is determined by quantum mechanics. The development of new chemical processes, new materials and new drugs is inseparable from quantum mechanics. It can be said that it is better to ask what quantum mechanics can't do than what it can do!