The free tier of IGDB has a rate limit of 4 requests per second and they will block you if you try to download the entire database, so this may be a dead end anyway.
Found a 4 megabyte dump that seems promising though it's from 2018 so outdated.
https://gist.github.com/LeWawan/5858a9e7bef0f3dc4a79ac8bc1e3380c
Another one, a 68MB 3 year old "dataset" for AI training that seems related to IGDB.
https://www.kaggle.com/datasets/anudeepvanjavakam/igdb-api-data/data