I don't understand why people would keep a mortgage just for the tax break. I get using the tax break if you have a mortgage, but keeping one doesn't make any sense. Mortgage interest is a tax deduction, which reduces your taxable income. So if you pay your bank 10k in interest, you don't pay taxes on that money, which for most of us would be about $3300. But your net loss is still $6700 out of your pocket. Or you keep your 10k by not having a mortgage, and yes you'll pay the gubmint $3300 more dollars, but you still get to keep more money in your pocket in the end.

Plus you can only write off your home mortgage interest if you itemize, and given the new tax law the vast majority of people are now just using the larger standard deduction anyways.