The Silver Empire was indeed to blame for this. Because they manipulated their Zones so that others couldn't learn their secrets, their Variant Zone appeared in an obscure part of their Empire rather than an easily accessible location. As a result, a Zone that might have turn their fortune around fell into the hands of three small families who were still fighting over it to this day.
According to the history, the ultimate treasure of the Variant Zone wasn't claimed by any one of the families. Instead, it ended up split, with the Radix and Midas claiming one half while the Florer family gained the other.
Due to the treasure being split, neither group could gain the full and true benefits and the result was what they saw today. Neither family was able to rise up to the level of the Silver Empire, but they weren't necessarily weak either. In terms of the power scaling of this Sector, they could be considered to be in the dead center, maybe a tick above.
