BOTFB have made enough goa trance(more characteristic example I can think of is the track Mr. Fantastic) or , generally, psy tracks with goa elements with them, but no track is goa trance in Demonoizer album, if you have heard. All of the artists I listed are different from each other, as they have their own characteristic sound.
I agree that the difference between Derango and X-Dream is extremely obvious.But, to add to this:
the difference between BOTFB and X-Dream is extremely obvious.
the difference between BOTFB and Psykovsky is extremely obvious.
the difference between Derango and Psykovsky is extremely obvious.
the difference between Electrypnose and Psykovsky is extremely obvious.
I think the above replies to you too. I agree they are very different, but both create dark night psytrance music. Psykovsky and Electrypnose sound equally different to me too, as I implied in the examples above.
For me all of the above have made dark psychedelic trance.
Also, since many say that 'darkpsy' trance producers have no talent, you should check Electrypnose's downtempo/psychil/IDM album Subliminal Melanchoolies or Psyfactor's Endless Universe. That's how I like to respond to invalid arguments.