Why doesn’t PS3 support Soft Subtitles?

A ridiculous omission from the console which supposedly ‘Does Everything’. I imagine it would be quite easy to add this feature. It already supports DivX subtitles, why not add support for all popular soft subtitle formats?

(By ‘Soft Subtitles’ I mean where the subtitles are in a separate file from the video, and you can play the video with the subtitles in that file, replacing any that are already in the file.)

e.g. If i was to try and watch a japanese video file, and I wanted english subtitles, I would simply download subtitles from a subtitle website so I don’t have to waste time and money looking for a version with subtitles. Despite them working on windows media player, etc. to make them work on PS3 I would have to convert the video, which takes a long time and results in quality loss.