A HDD has 1 controller chip and that controller is relatively simple compared to the controller chip on an SSD, its certainly a lot smaller and on a less advanced process because it has to deal with ~200MB/s not 15000MB/s. On top of the controller chip a 2280 NVMe SSD will have 4 or 8 memory chips as well, which are on a recent process and have many many layers stacked together. Then the SSD will also often have a DRAM chip as well. An SSD uses substantially more silicon than a HDD does.