Great article and fantastic work, though the commitment to stick with the ancient DCC software of the era (genuinely admirable), is an immense amount of pain, for no real gain that I wouldn't dare to try. Modern Blender can be extended to import/export legacy formats like DirectX 8 .x and N64 Homebrew for example have great asset tools all working in modern Blender, with a big community behind them. FBX was originally a (Kaldera) MotionBuilder format only back in that era and 3ds Max support for it didn't come until around version 8/9.

I'd say there's a way to build a modern asset pipeline for the OG Xbox where you can leverage USD (well supported in all modern DCC), and then build tooling/viewers around it to process/split/export everything out to DirectX 8 .x in a much more manageable way. Makes artist collaboration a lot easier (modern tools with guardrails inplace), and can measure and keep metrics on everything (every KB counts with 64MB RAM).

All these old versions of Maya, 3ds Max and Visual Studio are just a total liability now. Licences for them can't be activated, and even if they can, it's a lot of backflips to get Autodesk to help. 3dsMax/Maya 8 and earlier barely work on Windows 10/11 now (Vista changed a lot for desktop apps) and even Visual Studio 2005 needed to be patched to support Vista!