FPGAs have no particular advantage. You could dedicate a chunk of their resources to implement a softcore CPU but it'd be several times slower than a real CPU.
The random programs change too quickly to just implement them directly on an FPGA. Reprogramming the entire chip like that takes too much time.
The random programs change too quickly to just implement them directly on an FPGA. Reprogramming the entire chip like that takes too much time.