It's odd really.
I get the impression that somebody at FDev intends that the galaxy be a sort of "Mad Max", post-apocalyptic, fallout style environment and that would explain why ship design reached a pinnacle and then never progressed any further.
However, I also get the impression that this isn't an officially-endorsed paradigm and that's how come we've ended-up with superpowers and corporate entities co-existing with drug-empires and outright lawlessness.
I kind of wonder if nobody at FDev ever bothered to call a meeting and lay all this stuff out to ensure there was "clarity of vision" across the board.
Or, perhaps it's a case of the FDev developers wanting to quietly do something which might not exactly comply with David Braben's vision of what the game's supposed to be?
The Elite galaxy has always been a weird one, technology seems to have stagnated in some areas but not in others, technology was pushed back at one point by apocalyptic war and a high number of people in it seem to be psychotic.