Literally all I want is to extract the models and textures to import into another program for examination. But I can't find any information for modding gamecube games. Has it become lost knowledge at this point? Have people given up?

http://aluigi.org/bms/sims_bustin_out.bms

This is the BMS script that allows unpacking .ARC from Gamecube Sims games, including Bustin' Out, The Sims 2 and The Urbz.

Sadly, IDK how to convert the extracted textures and models into any other format