I already pointed out that you pay the other half of SE tax, but that’s at most 7.65%, and since SS is capped, for many high-income self-employed workers it’ll be less.

And yes, you pay income tax, but no more than you pay as an employee, so it’s not relevant here.

In fact, you now almost certainly have a huge advantage if you’re self-employed: in addition to being able to write off more and save more for retirement pre-tax ($55k), you now get a 20% deduction of your net profit if your taxable income is below $157k single / $315k married, which most self-employed folks will be.

Healthcare is still by far the biggest cost difference most people will face but even if you add all these things up, they don’t represent anything even remotely close to 50%.