True
Being fair, regardless of ED's many, many flaws, there's just nothing in the foreseeable horizon that could kill ED, or even compete in the same genre.
Even X4 is a different kind of game. The only released game in the same genre is Evochron, and although it does many things very well and ED could definitively borrow some inspiration from it in certain aspects, as a whole it's just not on ED's level.
As for Starfield, it will most likely be a space based first person RPG game. Skyrim in space (not complaining). I'm eager to see it and play it, but will most surely be a completely different kind of game than ED.