Earlier quoted context omitted.
They can deduct the employer share though? Or is that just self-employment taxes?
SE tax is the employer share, and its a bit complicated. As a 1099, you are required to pay the full SE tax generally minus (a couple?) deductions. But then, you are allowed to deduct half of what you pay in SE tax from your income for regular income tax. The SE tax is also paid I believe only up to some income limit. Then, there's the Medicare tax on top of that, which is not income-limited.
> SE tax is the employer share, and its a bit complicated
SE is equivalent to both employee and employer share, which is why you get to deduct half of it, equivalent to the employer share (which is not included as taxable income for other workers, either.)