Why exactly doesn't HTML5 Media Source video work on IOS?

Question

It seems both (HLS and MPEG-DASH) use the same the Media Source Extension API. So why does HLS video only work on IOS. Why doesn't MPEG-DASH work on IOS? What is the core difference making this "http://nickdesaulniers.github.io/netfix/demo/bufferAll.html" video not work on IOS? Where is the problem? Is it the new MediaSource, .addSourceBuffer, .appendBuffer, .endOfStream() or .mp4 file.

Answer 1

Only apple can answer that, and so far they have not commented.

EDIT: iPadOS 13 will/does support MSE. iOS 14.5 (iPhone) still doesn't not.