The publisher demanded it and put it in the contract. The developer had to stick to the contract. It also included plugins and scripts. The publisher claimed it would create liabilities. Can't say much more than that.
That's exactly how Blender came to be. He's talking about that one ^. Although Blender really is underrated, it doesn't have all of those features yet. It's getting close though. In the way of optimization, bloat, its interface, and python scripting, it's amazing. I was waiting to see how long it would be until someone…
Just imagine: a from-scratch, game-art focused application. No extensive animation options (just enough for games), no FX and simulation, no rendering other than GPU-baking, material system is purely focused on realtime viewing. Proper modeling tools to support High-to-low modeling, easy management of what objects to…