Upload Policy for Commercial Game CG and Diffs?

I've noticed that CG from many games often aren't uploaded here, despite the artwork being high quality. I'm trying to understand why this might be. Is it a lack of interest from uploaders, or are there unspoken rules (or approval difficulties) regarding commercial game CG on Danbooru?

Before I start uploading and risk having a bunch of posts deleted, I wanted to get clarity on a few points that more experienced contributors probably know well. I'd really appreciate it if anyone could take a look and share their knowledge:

1. Is CG from any game allowed? I found an old forum topic (topic #18919) from 4 years ago saying it's okay, but I wanted to confirm if this policy is still current.
2. If a CG has numerous minor variations (different facial expressions, clothing states, etc.), is it encouraged to upload all of them?
3. If I obtain the CG by ripping the game assets myself (not sourced from E-Hentai, SadPanda, etc.), what should I put in the `source` field? Just the game's name? Or is a link to the official game page required/preferred?

Thanks in advance for any guidance you can provide!

Yes, game CGs are allowed. Tag them with game_cg and use "extracted from game" or something along those lines in the source field. If there are multiple variants, tag them with variant_set and don't forget to parent the posts.