I use various types of alcohol and other chemicals extensively in my work in electronics and computers. They are very useful if you know what you're doing. However, blindly advising others to use them as a general cure-all can be misleading and could do more harm than good.
For example, organic solvents, including alcohol, can dissolve some plastics, seals and lubricants. Moreover, many such chemicals mix readily with water and often have a high content of water by absorbing moisture from the air. Even if the chemical itself evaporates quickly, the water is left behind and that can cause more problems.