OK. I went back to the electronic copies of all the worksheets, and here is what I found:
For 2016 return, Cap Loss Carryforward Worksheet, long term carryforward to 2017 was $47,043.
For 2017 return, Cap Loss Carryforward Worksheet, long-term carryforward to 2018 was $48,938.
For 2018 return, Cap Loss Carryforward Worksheet, long-term carryforward to 2019 was $45, 938. Note this was exactly the $3000 one may kind-of expect.
But...For 2019 return, there was nothing called a Cap Loss Carryforward Worksheet. Instead there was a "Federal Carryover Worksheet", in which Line 13a lists long-term cap loss as 0 (actually, left blank). I get the impression that when TurboTax re-organized their worksheets, my cap loss tracking fell through a crack.
