Originally Posted by Kurgan
The seeming stagnation is due mostly to authorial intent. Lucas's fantasy galaxy is like Tolkein's Middle Earth. It's a fun way to keep your universe basically unchanging. Sure the government changes hands, but everything pretty much stays the same. The technology changes only in matters of degree. Bigger fleets, bigger ships, more guns, bigger armies. The Death Star is like those little ball turrets on the LAAT, just scaled up by a huge margin, with the necessary power generation and defenses all there for you. A lightsaber is just a frozen blaster bolt or some such fantasy science.
Besides, the Star Wars stories only take place over a period of 35 years, tops. Where you get into problems is the Tales of the Jedi series which takes place some 4,000+ years before the movies. They decided to make everything the same as it was in the movies, only dressing people more like New Gods (DC comics series) and giving their tech the decorations of ancient Rome or Egypt (like Stargate). They have all the same stuff.. hyperdrive, lightsabers, blasters, etc. I can't really recall any technology in the movies that they didn't have in TOTJ (and KOTOR). They have planet destroying super weapons too. I don't care if they want to call it some "sith artifact" or what, the point is, it does the same thing. Either they lacked imagination, or they worried that people would not recognize it as Star Wars unless they put in all the same conventions, but they wanted to set it far enough in the past so that they wouldn't have to worry about stomping on the continuity of any of the established characters (of course you get some bungling with the history of the Sith and Republic, but oh well, retcon cannons at the ready, firing with both barrels!).
Perhaps you did not read much into the previous posts? Not that that's a bad thing, they ARE pretty long, I apologize for the length. D:
We're talking...4,000 Before the Battle of Yavin, right?
What happened to the other 21,000 years of the Republic? Did they just...not build anything in that timeframe, or everything was built for them?
21,000 years is a VERY long time for technology to change, be discovered, and evolve. The reason why the clothing from the year 4,000 BBY is almost the same as the clothing in 1 BBY is because of that timeframe, 25,000 BBY - 4,000 BBY, hypothetically. We virtually know very little about the culture of the Republic before the Knights of the Old Republic, and it seems very liberal to discuss these matters. However, one can argue that the 21,000 years before the events of KotOR culminated into the complete technological society of the Galactic Republic.
That said, it seems natural that the same clothing/weapons/technology exists in both eras because they reached the point of stagnation/technological limit. Why mess with a good thing? Why try and discover new weapons, because they basically had EVERYTHING they needed: Droids that did their work, bacta that would heal most wounds (or Kolto, if we refer to KotOR,) and an effective Police Force (READ: Jedi) that solved most, if not all, of the Old Republic's worries, especially during the events before the Battle of Naboo (READ: Stark Hyperspace War.)
It seems very illogical for the Old Republic to focus on developing new weapons. Besides the fact that the only new weapon that could be developed would be a System-spanning, even Sector-spanning, destructive weapon, capable of destroying many planets at once, or even a viral/bacterial weapon that would completely destroy a single ship's entire crew, leaving the opposing force to take the wreckage and implement it into their own.
But that's besides the point. There would be no need for the Republic to find a way to create such weapons, as they were indeed a completely pacifist government until the time of Chancellor Palpatine. Seeing as they had literally all technology possible, save for the cure for aging (Which may be unable to acquire in any society,) where would the Republic go from there?
And you forget, the Death Star is not a rehash of the LAAT, as they use completely different energy sources; the Death Star's being the most rare, and could only be found on Mygeeto, and the beams, while potentially the same, require different workings of technology. The LAAT came out of a single shoot/barrel-like expeller, while the Death Star's laser came out of a dish, and was composed of smaller laser beams.
In closing, the Republic simply reached the pinnacle of their society LONG before even the events of KotOR. We cannot attribute the stagnation of the Republic to 'Authorial' devices simply because it is not logical.