If you are familiar with the Halo series, there was a race that had developed technology to the point where it became redundant. Basically they had transcended the need for technology and became primordial deities.
In the same way, Star Wars might have reached its technology redundancy, as the only real developments are in certain niche areas and military science; both of which are used to further plot. The SW universe could very well develop further, as there are precedents for more advanced societies. The Columi, Gree, Kwa, and Taung were all advanced even more so. Finally, the Celestials are the epitome of tech advancement in the SW universe. In order for there to be a significant advancement in general technology, there needs to be a major discovery of some sort.