The theory behind this is to make the 360 cost prohibitive to mod. The modders are going to mod the 360 for entirely different reasons. For them, it's something to defeat. Play MAME is the lowest priority.
So, for the average gamer who wants to pirate roms. The most likely scenario would be to buy a used Xbox (or use yours after you get a 360), a modchip, and a big hard drive. Modding an Xbox is easy, well documented, and has a lot of benefits. Modding a 360 will just not be worth it. Why spend all that money to mod a 360 when a modded Xbox will be cheaper and perform all the same functions?
So, for the average gamer who wants to pirate roms. The most likely scenario would be to buy a used Xbox (or use yours after you get a 360), a modchip, and a big hard drive. Modding an Xbox is easy, well documented, and has a lot of benefits. Modding a 360 will just not be worth it. Why spend all that money to mod a 360 when a modded Xbox will be cheaper and perform all the same functions?