Primary residences are always protected from tax agents.
Primary residences are absolutely not protected from tax agents. They can and are sold to cover unpaid taxes. While it is true they don’t do it often and will sieze every other asset you own first, that commonly leads to loosing your home as well. Good luck paying your mortgage when you don’t have a car to drive to work anymore and all the funds in your bank account are frozen.
"if you have unpaid taxes, the IRS has the right to seize your home through a tax levy. If the IRS seizes your home for unpaid taxes, it uses the money from the sale to cover the cost of seizing and selling the property. Then, it applies the remainder to your tax bill. You can apply for a refund if there’s any money left. " taxcure.com/tax-problems/tax-levy/home-seizure