The world economy is in the crapper. Governments around the globe, bloated to the point of collapse, are desperately seeking new revenues. That has driven taxes and restrictions on trade to new highs.
So high that millions of companies and workers are choosing to go around those taxes and regulations.
There’s nothing surprising about this. The more barriers put between citizens and commerce, the more likely citizens are to just go around the barriers.
That’s why, historically, the United States has never averaged more tax revenues than roughly 18% of GDP. When taxes get too high, people find ways (be they legal or illegal) to stop paying them.
Black markets are just the free market bypassing overly-burdensome taxes and regulations.