I've been trying to find more shitposts/mashups to get working but lord has it been hard

You've just said it three more times, you're digging your own grave Jet. ALGORITHM BE PRAISED

Sorry for the brain vomit/rambling, I just wanted to say how much I love the Blank Century and want to see it applied in other works more. I'm definitely going to try incorporating it into my settings, for sure.

So, how do you "get around" that, if at all? You could simply limit the maximum age of beings, or maybe they're more persecuted! Or actively hunted!

Maybe the gods (or one god? or a group?) struck this time from the record and see that it stays that way! So many options.

Since One Piece doesn't have super long-lived folk (even giants only live a couple hundred years), the ability to limit info is more feasible. D&D and other settings have several beings who live for centuries, if not forever (elves, dragons, sapient undead, to name a few).

To have narrative weight in a campaign, its long-term effects ought to still be apparent (e.g., OP's primary antagonist, the World Gov't, has existed since the end of the Blank Century), and its importance should be reinforced within recent memory (e.g. Ohara, the active search for the poneglyphs)