Some of the things that might have succeeded but for the lack of tools supporting user-created 3D content include
- Second Life. There are tools, but they’re extremely difficult to use. Blender has bridged the gap a little, but not all that much.
- SGML, and then VRML. A broadly supported markup language for 3D was a good idea, but the fact that there wasn’t a lot of 3D geometry being shared meant that it never really took off.
- SGI. They were ahead of their time, and did some amazing things, but how many (SGI) VR demos did you go to where they only showed the demos that came with the system. The lack of tools meant that there wasn’t enough 3D content to justify the cost of the hardware.
- 3DTV. There’s little 3D content being broadcast, and that may improve, but you’d have to suspect that until the content creation process gets a lot easier this wave of 3DTVs will suffer the same fate as the last.
The list goes on, but you get the idea. There is a lot of 3D capacity out there, and with HTML 5 there will be even more. All that’s missing is the tools.