If you reeeeally want to stretch, they do have rules about pricing things lower on other platforms. Like, you can have a sale on your website that makes it cheaper than Steam, but can’t have the base price cheaper there than on Steam. That’s about it.
You can’t sell the free generated Steam keys on other platforms lower than on Steam. You are perfectly free to sell the game on other platforms for less than Steam.
If you reeeeally want to stretch, they do have rules about pricing things lower on other platforms. Like, you can have a sale on your website that makes it cheaper than Steam, but can’t have the base price cheaper there than on Steam. That’s about it.
Disproven many times over.
You can’t sell the free generated Steam keys on other platforms lower than on Steam. You are perfectly free to sell the game on other platforms for less than Steam.