The world keeps flip flopping between serial and parallel.

Back in the day parallel ports were awesome because they were effectively 8 serial ports in parallel (sounds awesome right? 8 times the bandwidth)

But then some dude came along and USB did 100X the bandwidth in a serial bus. Then other dudes were like "okay great now let's put multiple USB data pairs in parallel" and boom USB 3.2 was born. Parallel again. USB-C is effectively a UPB.

Parallel ATA was the shit back in the day for hard drives but then Serial ATA replaced it. Now we're at NVMe which is parallel again with 4 PCIe lanes.

CompactFlash (parallel) -> SD (serial) -> UHS-II (parallel), same story

BNC cable ethernet (serial) -> 100-Base-TX (parallel) -> fiber (serial) -> fiber bundles (parallel), same story