While I wouldn't say it's impossible for the big factories to manufacture bathyscaphe, I think it's not likely anytime soon. Here's Why:
First thing you have to know is that bathyscaphe unlike fifty fathoms has displayback, so decorations will have to be done to resemble the gen. Both the Blanpain fifty fathoms and bathyscaphe use their in-house cal.1215 movement, which is a 30mm x 5.65mm movement. The fifty fathoms Noob makes uses the 2836 movement. The thing is, if you know your movements, all of the mass-manufactured movements are 26mm! That includes the clone 2824, 2836, 2892, Miyota 8215, 9015 etc. because these are smaller smovements, the balance wheel will never be in the right place. 2nd of all, the position of the balance wheel will also never be correct, as the gen is @ 5 o'clock, and none of the movements can do that.
However, many of the panerai & audemar displaybacks have the same position problem, and they're still being made and sold. Well, a wrongly positioned balance wheel may be overlooked by someone who's not an expert at identifying gens and reps, but the obviously smaller movement in a huge 45mm case will always appear weird. Then there's also the problem of demand, which I think is the biggest problem. If you have a huge demand for a watch that is wrong, people who cannot tell or don't mind will still buy it. But in the case of bathyscaphe that has a very small following combined with displayback that can never be perfectly replicated, there's just no incentive to have it made!