It's not as simple. My country (UK) has skilled workers visa that has wage requirement set often at half the market rate for given job. For instance, company can pay a software developer as little as £35k.

Given that it is much more expensive to gain skill when you are a native, the government somewhat pulled the rug from underneath the locals who spend a lot of money to go to uni etc and were hoping to have a decent return on their investment in education.

This also creates disincentive for locals to learn these in-demand skills.

If you combine this with the fact that companies can rent out these cheap workers at £500 or more a day, while avoiding paying taxes it is a poor deal that only benefits big corporations.