Soldering small stuff can sometimes be easier, because at that level surface tension will do the job for you. So hand soldering 14 pins on a small size TSSOP package can be faster than soldering a SOIC (through hole) package (google drag soldering — just be careful with that in certain parts of the US \s)

The hardest part with cables is to prepare the strands and keep them in place. For this you can build fixtures.

There's a pretty decent chance it is a mix of both.

USB-C connectors with pre-attached PCBs ("paddle cards") are widely available[0], and are created by a machine. Aligning the cables with the paddle card is quite tricky to automate, so humans are still used for that.

[0]: https://www.lcsc.com/product-detail/C62322.html

> are they really hand-soldered?

Probably not, at least not in the way most people think of hand-soldered. There are hybrids where a human drives the soldering iron electronically rather than holding it in their hands, although even this the rate of defects would be so high it would make it impractical at even a small scale.

Typically you have a stencil that you squeeze the solder paste through and then you put the IC on top with a tweezer and bake the whole thing with something like a hair drier. It's not that difficult to get good results without using an expensive pick&place robot.