[onion2k]

The Unity WebGL engine is about 5MB gzipped. You won't get a web export smaller than that, but you shouldn't need 20MB of assets on top of it for a small game either.

[bhouston]

For a point of reference, Three.JS's source code hovers around 100KB gzipped, sometimes more, sometimes less. That is a factor of 50x difference.

[greggman]

three.js doesn't have 1/50th the features of unity. three.js is great and ive contributed to it but a game engine is a lot more than just a renderer.