You're also paying for 12 Thunderbolt 3 ports. They really could have made some of those optional since there's PCIe slots too. In addition to expensive parts

You're also paying for 12 Thunderbolt 3 ports. They really could have made some of those optional since there's PCIe slots too. In addition to expensive parts I believe TB3 requires licensing costs too but I'm not sure if Apple has to because I think it was partially created by them.