@Jo_Ndule
If Marco has a bounty above Luffy, their is no more room anymore to don't see him as special. Not like King,Queen and Jack who are also known for their evil destroying of cities, Marco is totally the opposits. The one guy who stay always with WB and don't destroy cities. With would mean if he would get a bounty of 1.5b-2b it would mean he only get his because of his power/strenght not like Queen or Jack.
Like similar how Katakuri get his bounty,because of his own power strenght.
If Marco pass Katakuri and King bounty by a mile and coming close to 2B, their is no more room anymore and it could easily said that Oda clearly portrayal him as special and as a low top tier and not a high high tier.