Famiboards

Valve updated their Rules and Guidelines under their Steam Onboarding site and added the following point:
13. Applications built on blockchain technology that issue or allow exchange of cryptocurrencies or NFTs
under their "What you shouldn’t publish on Steam" guidelines.

Today, game creators are reporting that their games utilising NFTs are being removed from the platform. Below, the Twitter account for Age Of Rust – in which players “collect in-game NFTs” –
announced that “Steam will be kicking all blockchain games off the platform, including Age Of Rust“.

Click to expand...

- NME


Based on what the devs in this twitter thread are saying, the reason for Valve to removes these games is,
because they don't allow items that have real world value on their platform.

Source: https://www.nme.com/news/gaming-news/steam-is-removing-nft-games-from-the-platform-3071694