It's all about the $$$ and the community. Blender started as a commercial project too. I was already using it in the 90's alongside POVRay.
The good thing is unlike in the photography or the print industry there is no real industry wide vendor lock-in when it comes to formats in 3D, so it's always possible to create a challenger.
Right now Godot isn't really on par with Unity, but it could become the de-facto game engine for Blender in the future if Godot allows deep integration with the former.
> there is no real industry wide vendor lock-in when it comes to formats in 3D
Mmm, Blender had a lot of problems having to reverse FBX from autodesk, which AFAIK is or was a de-facto standard. About open standards, I kinda hate xml, so I didn't like Collada much. I'm looking forward for knowing more about glTF[1]. Thankfully Blender 2.8 had the official add-on from the beginning.
The good thing is unlike in the photography or the print industry there is no real industry wide vendor lock-in when it comes to formats in 3D, so it's always possible to create a challenger.
Right now Godot isn't really on par with Unity, but it could become the de-facto game engine for Blender in the future if Godot allows deep integration with the former.