What is the MAIN reason population levels in the Sahara are so low?

The Saharas climate consists of basically two sub climates a dry subtropical climate in the north and a dry tropical climate in the south.

Because it is a Desert

Explanation:

Since it is a Desert, it is very hard to live there, as there is little water, and hotness. It is very dry and there is little food, as crops cannot grow.

trade regulation is a field of law, often bracketed with antitrust (as in the phrase “antitrust and trade regulation law”), including government regulation of unfair methods of competition and unfair or deceptive business acts or practices. antitrust law is often considered a subset of trade regulation law. franchise and distribution law, consumer protection law, and advertising law are sometimes considered parts of trade regulation law.

in general the theory of economics says that the more open to trade a country is the better   the result for the same country and the whole economies.

in real life countries impose taxes, quotas, etc which is not so good for the economies.

this kind of commercial war between the usa and china is slowing down the growth of the whole world so we can say that it is a draw back of trade regulations. and the free trade agreements are benefits of trade regulations.