I think it's a perspective thing. You are looking at the rate of false results, so given a particular type of input what rate do you get it right? For negative

I think it's a perspective thing. You are looking at the rate of false results, so given a particular type of input what rate do you get it right? For negative ground truth your possible outputs are "false (positive)" and "true (negative)". I agree it can be confusing, but I think people would also make the opposite mistake if it were defined differently.