why not have the 50% of people who pay nothing pay something?
Do you mean working people? If so 50% don't pay nothing. Everyone who works pays at least an effective 15% payroll tax (including the employer's match)
the post is about raising income taxes not payroll taxes and yes 50% pf people pay no income taxes. And an employer contribution to Social es in just that, the employers tax not the employee's tax.
You didn't say income taxes, you said 50% paid nothing. That is false. I clarified.
Many economists contend that the employers contribution would be more salary to the worker as it is a cost of labor. But even without it they pay about 7.5% directly.