User blog comment:Legionwrex/What do Reapers do with the technology they harvest?/@comment-3228423-20121218060826/@comment-4950455-20121218085423

We don't know actually have enough information about the history of Citadel civilization to call it technologically stagnant. We do know that it hasn't really approached the limits of what technology in the ME-verse can do, but there isn't really a baseline to compare the current era's rate of advancement to (although it is, admittedly, almost certainly faster than normal).