For me the issue is rarely foreign subtitles. The issue is almost always the inclusion of the "forced" subtitles in the main movie. It is extremely difficult to find just the "forced" subtitles for a film or TV episode and I personally find it EXTREMELY annoying to have to toggle the subtitles on and off manually just to understand a short passage of Japanese dialogue in a movie like Kill Bill, or the Spanish bantering in an episode of Breaking Bad.
This IMHO is a very big shortcoming with formats other than MKV. With MKV, when the episode/movie is ripped by MakeMKV, the forced subs are put into their own separate sub track. I can then either mark this track as "forced" so that most players display it automatically, or if I really want to be sure they will show up, I can encode the movie with handbrake and burn those subs in.
As a bonus I can still have the entire original (and very high quality visually) PGS subtitle track included, which I can then toggle on and off if I had trouble with some of the dialogue.
It is a major drag to me that Apple and other manufacturers have ignored MKV format when it does so much of what is needed for media playback.