Honestly, for several reasons, I don't really buy those explanations. Am I really supposed to believe that its so hard to come up with a 3W power supply (too bulky? For a Neo Geo owner? Yeah, right.) or a dual PCB? I really think that stuff could be overcome if people wanted it bad enough. Also, I think the earliest pirate MVS carts are only a year or two newer than the Neo Geo itself. Making a pirate cart isn't the whole picture, but its a part of it.
The most popular machines are always cracked wide open and pirated to hell and back. I'm sure it wasn't exactly a breeze developing the first DS flash cart, but since the DS is the most popular system in the world, its super total cracked.
The most do-able solution would be something, like the guy said, that ran off RAM and to just have what's in the flash loaded as needed. I'm not the person to do this my any means, but I think painting a picture of the Neo Geo as impossible to run back-ups on serves the Neo Geo mystique, and now that the system is finally dead it needs some mystique pumped back into it. Kind of like how fans of classic American muscle cars just can't come to grips with the fact that their shit was fine for its day, but its just slow as hell compared to the new stuff.