Why do you automatically consider industrialization to be good? Equestria is not Earth, things are already much better then over here. Industrialization isn't needed at all, and they've already surpassed human achievements in, well, honestly I'm having trouble coming up with stuff that we've done that actually is impressive in comparison. The Internet I guess. But that still not that impressive when put beside literal time travel and weather control.
As for a space age, they literally control the movement of the moon and sun. I'm not convinced there is a space to go to but if there is, I'm pretty sure they can figure it out without industrialization. Which for that matter, isn't really associated with the space age?