This resurfaced again here: GIS-SE - Answer to XY points not displaying – now deleted after this discussion.
I want to point out another issue with these kind of edits, and more importantly encouraging them, besides the fact that it contradicts with the community's purpose which is asking/answering on-topic posts and not translating them.
When dealing with questions, as stated in other answers, closing is the best approach as we may not be able to get feedback from the OP if they are not familiar with English (they may not even be able to accept a correct answer, if they don't understand it).
In case of answers, there are some examples of non-English posts that will be salvageable through minimal edits. Like when OP says (in a non-English language) "Try the following" and then the rest is code or something that does not need translating. In these cases, I am fine with the edit to make it in English, while still not advocating for/encouraging them.
But in the link above and many other threads, we probably need to use a translating service and edit aggressively. That causes two problems:
Mostly, these services does not translate technical terms correctly and translation needs proof reading which should be done by someone who not only knows that language and English but also understands the subject and the answer completely. If the user who edits lacks any of the aforementioned skills, their edit can potentially misguide other users. Please bear in mind that these answers are mostly posted by users who are not regulars of the community (that's why they are posting in another language in the first place) and so they probably won't circle back to check whether the translation is accurate or not.
Second issue here is the nature of that edit (refer to What guidance should be given when edits are rejected? for more details). That edit is an aggressive edit and it conflicts with author's intent (or at least, we cannot be sure if it does not). Let's say one is familiar with the language and knows the subject, so the prior problem does not apply to them. Then, in my opinion, their edit can be categorized as an attempt to reply and should be posted as another thread.
All in all, I don't think it's a good idea to edit these kind of posts.
N.B. As I mentioned a post on GIS community, I want to also point out that it seems in that community there's a will toward translating rather than closing/deleting (reference: MetaGIS-SE - Handling questions posed in a Language Other Than English (LOTE)?).