Everyone who now gets health insurance as a “benefit” would be able to afford to buy it, if the income tax were abolished, and all “benefits” were converted to salary.
And if a company stopped paying health insurance (which many will be soon), what makes you think they will pay more in salary?
That won’t happen. In fact, from what I have heard some will pay less, because of the “tax” (which will be collected from payroll).
Very few, if any, companies pass on the savings to their employees. That is not good business practice, and will get you in trouble if you are a publicly traded company. The stock holders want more return on their money, not less.