I think you missed the point.

Compare Her Reputation with Luffy's and i say it's not even close even though she can read the poneglyphs. Luffy reputation far exceeds her own so that plays a role.

Like, so many people write off Robin's bounty as the World Government not wanting to draw attention to her importance. And then you have other theories where Luffy just obliterates this logic. Remember, 5.6 billion is above Roger, who has the highest pirate bounty in history and this would be an increase of 4.1 billion. To put that number into perspective, that is a difference that exceeds Shanks entire bounty.

I mean, it's just so massive that it feels out of place and further make certain bounties hard to grasp.