With how many authors shoe horn in an isekai premise to an otherwise normal fantasy wherein the isekai aspect is never relevant past the first chapter, the revelation that this isn't actually isekai is refreshing.
He was told he has implanted memories, but it seems to be exclusively raw technical knowledge rather than anything we'd typically call a memory; being in a classroom learning, or in a lab/workshop discovering the knowledge or any other events, relevant to technology or not. I'd guess figuring out just how far in the past his knowledge is from and why it was all lost will be a major plot point moving forward.