I don't understand how people can say that demand is greater than supply or the other way around. Aren't they exactly matched, using the nifty concept of salari

I don't understand how people can say that demand is greater than supply or the other way around. Aren't they exactly matched, using the nifty concept of salaries? Anything else seems absurd. The demand for skilled software engineers working for free is infinite. The supply of skilled software engineers willing to work for one million dollars per month is much greater than the demand for such.