Sui Generis / Examina seemed well advanced already by the time the Kickstarter campaign started
The content shown in the pre-alpha Sui Generis videos was not gameplay, it was placeholder assets put into the game engine for demonstration purposes in order to give people an idea of what Bare Mettle were trying to create with SG. There weren't almost any gameplay mechanics in place yet and the combat was barely functioning -- it required a ton of hacks just to make it somewhat functional so they could record the demonstration videos.
When the SG pre-alpha vids were recorded the game lacked the armor layering system, the player creation system, the player couldn't gain experience points and there weren't any skills to train, the game lacked hundreds of art assets which have since been created, the animation/motion synthesis was barely functional, the number of weapons and armor was quite limited, the AI was barely functional, the pathfinding wasn't very functional, the dual wielding wasn't anywhere near complete and back then it basically consisted of randomly flailing around instead of intelligently using both arms like in the current version, the NPC behavior system hadn't yet been implemented, most of the sound effects and music weren't created/implemented... I could list literally dozens of additional game mechanics which have been worked on and added after the SG pre-alpha vids were created.