Public money indirectly comes from the most profitable companies, so it's not as bad as you suggest. I'd also say there are worse freeriders of academic research in the economy than big tech.
Are you talking about Elsevier, et al. How dare you?
(In the U.S.) Corporations only account for 6% of federal tax revenue (https://taxfoundation.org/data/all/federal/us-tax-revenue-by...).
And probably the most profitable companies are the ones that are the best at skirting corporate tax law...
rates become high fast enough for employees of sme to start paying substantial taxes, and payroll taxes don't have progressive rates, and ss is actually regressive tax.