>>5371705From my understanding the Knight Steeds (What is called from the DAoT the Knight Suits) forces the wearer to become more rigid in thinking an naturally conservative to the point that they reject a lot of technology.
One could easily see things as a building of tradition via the Manifold. Unlike normal cultures, each noble is subject to the feelings and experience of their ancestors that were all encoded into a Knight Chassis. Add in that the Knight Machine Spirit tends to see itself as noble, protective, and lawful causes Chivalry to become a staple. However, due to the innate aspects of Conservativism, the new Nobility will never allow change as it goes against what is encoded within the Machine Spirits of their Steeds.
Now this causes something two fold. One is that the Knights will force technology to stagnate and because the Federation was very decentralized no one could stop them. One would add in that at some point these Knight Worlds become fucking impossible to invade because Knights are terrifying. The Dominus is a fucking mini-titan for crying out loud. This of course is reason two, as thanks to their stagnation Knight worlds have a vastly higher chance of surviving Old Night which is reflected in the Stratagem 'Survivors of Strife' and 'Pains of Old Night'. In this Quest Dutonis is a perfect example of a Knight world surviving.
So, Tech. The Knights due to their stagnation will not look into anything greater than what the STC initially gave them. STCs were always built specifically to generate plenty of stuff to sustain a colony for further exploitation. This would place it squarely in 1800's technology since that tech could be fashioned by hand without the assistance of a machine, but also be exploited enough to cause population booms or export to a galactic entity.