There’s Shadertoy and Three.js although the main reason we don’t see many 3D web games is both Steam being where the money is, portability to consoles and asset

There’s Shadertoy and Three.js although the main reason we don’t see many 3D web games is both Steam being where the money is, portability to consoles and asset size. The latter in particular makes the web unattractive to game developers used to delivering gigabytes. It’s a different mode of production and people won’t make that switch en masse until someone proves it out. Now Blender is really good we’re seeing a lot more indie games exploring low-poly 3D aesthetics. Further the increasing viability of using more compact formats like SDF hopefully means we see even more people realising they can actually build something on the web.