But it also makes me a little bit sad. The original parallel port and even ISA interface seemed so simple by comparison, with less layers of abstraction. Just run a wire, and write to a port.
I remember when I was a kid, I found a breakout board in an electronics store's random clearance parts bin, with an ISA header on an edge. On a whim I took it home and wire-wrapped a 7-segment LED onto it. Power and ground were easy. Each segment was hooked to a data line, through a simple buffer IC. I cheated and used only a minimal number of address lines to feed the enable port (guessing through a simple AND gate or something). I was amazed when I wrote to that address and it worked the first time!
I look at a protocol like USB, with hundreds of pages, and instead of that curious excitement and enablement I felt back then, I feel a bit overwhelmed.