Fixed cost in accounting means all the costs except for the cost of making the next sale, which is called marginal cost or variable cost; so for example the marginal cost of a sale of IntelliJ is the cost of accepting payment, delivering the software somehow (i.e., mostly server costs these days) and support costs.
Marginal cost of a car in contrast is the cost of the materials that go into the car plus the cost of any parts or subassemblies not made by the car company.
So, your "tech is special because the fixed costs are extremely low compared" is false.
Programmer salaries are fixed costs because if you suddenly start selling twice as many licenses each month, there's no need to hire more programmers or have your existing programmer work twice as much.
Marginal cost of a car in contrast is the cost of the materials that go into the car plus the cost of any parts or subassemblies not made by the car company.
So, your "tech is special because the fixed costs are extremely low compared" is false.
Programmer salaries are fixed costs because if you suddenly start selling twice as many licenses each month, there's no need to hire more programmers or have your existing programmer work twice as much.