It is quite conspicuous how differently German and English is subtitled, in that commercial or professional English language videos are almost always exactly subtitled, whereas the German videos I have seen struck me by how loosely the subtitles matched the actual speech. It is my suspicion that at least some of this difference has to do with a fundamental difference in how the native speakers view their languages. I think this might be an interesting manifestation of a fundamentally greater flexibility and variation that the German language has compared with English. German thereby intrinsically encourages native speakers to paraphrase to a greater extent than does English. Does this notion have any validity?
English texts are shorter than German equivalents, as many multilingual texts (e. g. CD-booklets) show easily. (I18N experts translating GUI texts can surely confirm this.) Since length of text requires screen estate in subtitles, there is a strong urge to simplify texts, so not too much of the picture is covered.
I found a nice article on Science Advances by Christophe Coupé, Yoon Mi Oh, Dan Dediu, François Pellegrino: "Different languages, similar encoding efficiency: Comparable information rates across the human communicative niche", see especially figure 1, lines marked DEU, where it is shown, that German has a significantly lower communication rate in bits/s (IR, right column) than English (marked ENG).
Due to comments: I do not claim that this is the only reason, but have some doubts, that a single reason can be found. Everybody may feel free to contribute by adding a further answer.