I think quite cheap models will probably work with translation (I think for many use cases Google's now fairly old tech works well enough and is free?).
The main problem is I think you're assuming because the current translation market is large (I'm just going to assume it's ~100B in size just from a cursory search), then it will remain large with LLMs. If LLMs are much cheaper than humans, even with a lot of growth in translation volume the total spend may not compensate for it (again most of the volume will probably be using almost free models?). Another is assuming that because something is valuable you can charge a lot for it. Like, oxygen from air is extremely valuable to us. If oxygen somehow depleted we would die almost instantly. It does not mean everyone goes around purchasing oxygen or even less that you can charge absurd amounts for it.
The main problem is I think you're assuming because the current translation market is large (I'm just going to assume it's ~100B in size just from a cursory search), then it will remain large with LLMs. If LLMs are much cheaper than humans, even with a lot of growth in translation volume the total spend may not compensate for it (again most of the volume will probably be using almost free models?). Another is assuming that because something is valuable you can charge a lot for it. Like, oxygen from air is extremely valuable to us. If oxygen somehow depleted we would die almost instantly. It does not mean everyone goes around purchasing oxygen or even less that you can charge absurd amounts for it.