Those costs are pretty low FWIW. It takes into account the cost of the individual parts however it does not include the testing/prototyping and designing all the variants of said parts.
I'll give you an example. McLaren are coming into this weekends British GP with 3-4 new rear wings and other aero upgrades different from the previous race.
The FIA also have a habit of changing rules mid season ( to "cut costs" ) which actually just mean more design work for the team which costs exponentially more than keeping the original rules would have. The teams have been working on exhaust blown diffusers so far this year. Basically when the driver lifts off throttle they map the engine timing to still force exhaust gases out and "blow" the diffuser for more downforce through the corner. They decided that this wasn't "right" and made the teams redesign their engine mapping and whole aero package to account for it.
Such hidden costs are never quantified.