More and more games seem to suck on thier own, but can be great with mods. You have entire platforms like roblox where all the games are more or less mods. How long until the platform itself is community created and managed and the viability of games created by companies dissappears?
So, basically you’re describing open source, public domain game development (rather than just an open source engine like Godot) by the sound of it. This does happen, games like Luanti or Dungeon Crawl Stone Soup, but very rarely. Unlike mods, which tend to be small, quick-and-dirty projects, game development is usually much larger in scope and more difficult. It’s normal for the process to take years of work from a collective of skilled developers and artists. That amount of work is usually just too much for someone to willingly give away for free.