That is still technically true, but it requires filing your taxes with "itemized deductions" wherein you provide a complete list of all the things that you can deduct from your taxable income before calculating the tax owed. Stuff like mortgage interest, charitable donations, medical and education expenses. Back in 2013 up to 30% of tax filers did that. Mostly this was done by higher income people who had enough income and deductions to put them over the default standard deduction.
The "standard deduction" was increased in big changes to our taxes in 2018, and since then only about 10% of filers itemized. So mortgage interest isn't usually paid with pre-tax money anymore by up to two thirds of those who did it before.
The other reasons for carrying a low interest rate mortgage are still true.
It could just be that you are in a higher cost housing market, or have big charitable donations. But also, yeah, you're probably also kinda loaded. ๐
(at least when compared with the median American)