[mschuster91]

Using stuff like the pipeline stage is really bad imo, because it may prevent your game from running successfully if it is decided on a later stage to either upgrade the internal hardware (like it was done with the shitload of PS3 variants) or it is decided years later that the successor console should be able to play legacy platform games.

[JonathonW]

The first of these games was released in February 2004, late in the GBA's product cycle. At that point, the Nintendo DS hardware would've already been pretty much finalized (it released in Nov 2004), so they already knew what things looked like for backwards compatibility (the DS includes the GBA's ARM7 processor).

[klez]

I suppose that, since the cartridge was developed by Nintendo, maybe they knew there weren't going to be such hardware upgrades. Or they were just shortsighted.