Is it really my money if it's immediately going to the government before it hits my bank account? Is it really my money if I am subject to fines, wage garnishme

Is it really my money if it's immediately going to the government before it hits my bank account? Is it really my money if I am subject to fines, wage garnishment, repossession, or prison if I fail to give it to them? The government could greatly simply my taxes if income tax is just rolled up into payroll tax. My employer is already paying payroll tax on my behalf so why not just pay more of it and lower my salary to compensate?