If there’s no human effort behind this, what’s the point? You could just as well watch any of the zillions of video recordings of these demos. There’s no inherent value in "running natively in the browser". Never mind the vast irony in demoscene specifically being a celebration of human skill and creativity.
Well, there is a little advantage. Most recordings are not at the native framerate, and have compression artefacts (which impacts some effects more than others)
Not going to say anything about AI translations. But the video recording don't do justice for many of demos.
The effects in some of the demos simply kill any video encoder, only way to properly experience them is by running or emulating locally. Not that crystal sharp upscaled square pixels on modern display or poor quality CRT filters are very representative either, but it's likely better than blurry mess you get when video encoder tries to deal with high frequency details or random noise from procedural effects.