...In the computer world, AMD and Intel design and produce the same CPU that they sell at different price points depending on how the CPU has been frequency "locked" ( or "crippled" as some might say ), and this has been a normal part of the CPU business for several decades now.
If you are not happy at how Panasonic has "locked" / "crippled" their GH-2 camera design you are free to buy a different camera. ( right now I don't see any real competitors to either the Panasonic GH-2 or AF-100 cameras )
From a purely technical point of view, Panasonic might have been able to fit more AF-100 features in to the GH-2 design, but from a marketing / survival of the company perspective this would be a bad idea.
If you are not happy at how Panasonic has "locked" / "crippled" their GH-2 camera design you are free to buy a different camera. ( right now I don't see any real competitors to either the Panasonic GH-2 or AF-100 cameras )
From a purely technical point of view, Panasonic might have been able to fit more AF-100 features in to the GH-2 design, but from a marketing / survival of the company perspective this would be a bad idea.