Are people really bothered by this? Matroska is hardly new and is well-supported in modern media players. It is also free open-source software, and technologically equivalent or even superior to MP4.

MP4 on the other hand is patent-encumbered, and supports DRM — not things people who take a radically different stance on intellectual property tend to appreciate.

But all that has nothing to do with the actual encoding of video. Matroska is a container format, so if you have an MP4 and a MKV video file encoded with the same audio and video codecs, you get the same quality. From what I understand from Matroska, it has better support and flexibility for including additional resources such as subtitles.

So what kind of ancient media player are people using that makes this switch relevant to them at all?

Does somebody know why they changed from mp4 to mkv?