The problem is no feature set will meet even 5% of the needs of most devs. Maybe you'd like to display a "model" of a city. Oh, too big, needs to be streamed,

The problem is no feature set will meet even 5% of the needs of most devs. Maybe you'd like to display a "model" of a city. Oh, too big, needs to be streamed, LODed, etc. Maybe you'd like to display a "model" of a forest. Oh, well, you need a terrain renderer that dynamically generates geometry from height data plus you need a specialized renderer to render the grass and bushes else the frame rate will be 1fps. You'd like to display a "model" of Waikiki Beach at sunset and you'd like to use a water shader with a sunset and reflections. You'd like to display a "model" of the Los Angeles mountains as viewed from downtown Los Angeles, complete with atmospheric ray scattering to convey the air quality. You'd like to render a fur covered animal and render fur, not just a texture. You'd like to render a "model" of a person with realistic hair. You'd like to render a "model" of wax candle with subsurface scattering so it actually looks like a candle. You'd like to render a "model" of camera lenses to explain refraction so you'd actually like them to refract. Engines like Unreal and Unity let you change the way they render because every situation requires different solutions. No generic "render a model" covers rendering all models. An API like WebGPU/WebGL lets devs add what they need. Oh, you say, we'll just add features to cover those use cases. Now Chrome will have features A,B,C, Firefox, A,B,D, Safari B,E. That will be hell for devs. An API lets people write libraries with features they need that work in all browsers. They don't have to wait for the magic day N years from now that all browsers finally add the feature they want. Further, people will keep requesting non-3D features "I want to have an <input type="text"> in my scene". "I want to have a <canvas> in my scene" that I can draw on in realtime. "I want to have a model that displays a <canvas> in my model so people can draw logos on their avatar's t-shirts". I want to play sounds in 3D from specific points in my model, etc. until this "model tag" has all of HTML and all of JavaScript inside Again, this is all better solved with APIs instead of trying to cram more and more and more features into a single tag. > The other challenge of doing everything yourself is that code is stuck in time. It's going to get very minimal benefits from browsers and devices getting better over time, it won't get native UI changes - in 5 years it'll look very dated, if it's still accessible. And neither will a model tag. In fact it will be worse. First off, when I put a model on my page, I want it to look they way I or my artist created it. I don't want it to change over time based on someone else's idea of how it should look.