> with about the same efficiency and just a little more code.

It depends. For some things, CPUs don't even come close. An XCVU13P FPGA can handle 1.2Tbps of full-duplex Ethernet @ 1 billion pps. And that part costs less than a grand at moderate qty, and with significantly less power consumption than a CPU that'd be capable of operating a dataplane at these speeds.

Sorry, I spoke pretty sloppily there.

The point I was trying to make is that the CPU is a general-purpose creature and doesn't really care what you want it to do. If you had a CPU that could handle 1.2Tbps of Ethernet packets at 1Gpps, it could do a whole lot of other things involving 1.2Tbps of data flow too, very easily, if someone wrote the software. And more. (But you're probably not getting 2.4Tbps out of it, no matter what you do.)

An FPGA can not. There's plenty of things that those XCVU13Ps just can't do, or would do worse than a $1 microcontroller. (Setting aside for a moment implementing a CPU inside the FPGA... which does actually happen in just about every large-enough FPGA design, which is its own discussion....)