Since those game are available in English through the Sega CD, it makes much more sense for hackers to put their effort into completely unlocalized games. Xanadu 1/2, anearth fantasy stories, and emerald dragon to name a few.
I somewhat agree with this, but you can't deny that Snatcher keeps coming up as a major topic time and time again. At the very least it shows that there is great demand for a translation, even if an English version does exist in the form of the Sega CD. The problem is, regardless of public demand you need to get stakeholders to buy into the idea (Ie. people with the talent who can do translation patches), and it seems most just go "play the Sega CD version".
Considering how often the subject comes up, I would have assumed someone would have just done it already to get the monkey off the translation scene's back. It would stop the Snatcher topic from coming up again and again, plus it would make (I would think, in my humble opinion) a large portion of the PCE community very happy. Not that they are owed anything, but just to say that the effort would be sincerely appreciated and not gone to waste.