This is still broken in the desktop application version 2020.r16.037.
I just added both form 1098's for a refinanced loan, and my refund went down by thousands of dollars for a no cash out refinance. This is broken.
This is also going to be problematic for people that have loans governed by the mortgage deduction limits, or are grandfathered. TurboTax doesn't look like it'll handle this well at all.
I went to forms view, but can't figure out where the background calculation for the mortgage deduction is done. The number entered in 1040 Schedule A doesn't seem to come from either of the 1098's. It also isn't the sum of the values in 1098. It isn't clear how it's being calculated, but it is clearly lower than it should be.
