You are the manufacturer or seller of a chip with a digital interface and you want to get your products into the hands of developers so they can experience how your chips work?
You can build a complete developerboard with a MCU and your chip or you could connect
your chip to an USB bus and let the developers connect it to their PC.
In both cases, the developers need to set up Software on their PC to play with your chip.
If you make your chip available as a PMOD module, you could make available a complete
Verilog development environment running on the RaspberryPi, and the devlopers can play with your chip without the requirement to install software in their PC.
The deveopers would not need to install or license those huge FPGA developer tools like Vivado
just to try our your chip.
Analog Devices is making available a lot of their chips as PMOD demo boards.
Linear devices is doing demo boards of their chips for FPGA boards