Some things a hobbyist might use one for:

* Experimental processor design. If you want to make a processor with its own custom instruction set, or modify an existing processor design, you need an FPGA to actually see it in action.

* Synthesizers and audio filters. You can do a lot of low latency signal processing compared to even a beefy microcontroller with an FPGA, so if you want to make your own synth sounds in hardware, an FPGA might make sense.

* Computer vision stuff. If you want to make some gadget that does some kind of image processing that is streaming from a camera, and FPGA would work, especially if you wanted it to be small/portable.

* High bandwidth or low latency SDR applications.

There's not much there for hobbyists past toy ISA design and basic digital logic design exercises unless you really stretch the definition of hobbyist. It's a steep increase in learning curve for power that most people will never use.

Electronic warfare is most commonly the disabling of enemy radio frequency equipment (radar, communications, targeting, etc).

Got it. So it sounds like this post is more for people looking to build products and choosing which FPGA to base them on.

A lot of people believe that the year of the "maker FPGA" is upon us, and that the only thing holding it back is bad vendor tooling, so there's a lot of HN posts about them as of late. The vendor tooling is bad, but more than anything, the use case just isn't there.

Given, this is just my opinion on the matter, so take it with a grain of salt.