[stopping]

It depends on what market you're deciding to operate in, right? Global market vs domestic market. In an era of globalization, it's a huge loss for an economically well-off country to close itself off from the rest of the world. Remember that businesses don't have any obligation to operate in your country if the local labor market simply becomes too expensive. It also means that a business is far more likely to leave critical positions unfilled because an available person with the required skill set literally doesn't exist (or is extremely difficult to find). The only way to find talent is to poach from other companies, but this is a zero-sum game and offers no overall economic benefit to your country.

In principle a well-implemented visa program picks up people with required skills rather than just simply increasing the size of the available labor pool to suppress costs of labor. If the current program doesn't achieve this, then it certainly requires an overhaul. But abolishment (i.e. closing the labor market to domestic candidates only) doesn't do anything to further the economic health of your country.