I am answering.
Each warlord was pirate before joining warlord system. ( okay ? )
When warlord system has been broken , all of them have their indivual bounty. ( what we know that , because jimbei got 438 and crocodile has 100m before.)
Now.
Think about jimbei and crocodile case. Jimbei bounty hit 1.1 . Do you think this bounty was given for just beating who is who. Or jimbei bounty hit these range beacuse of he is known yonkou crew member anymore ?
Crocodile hit 1.9 billion berry. Do you think he got this bounty only sinking marine ships ?
Of course he got this bounty for creating dangerous thing.
Buggy had 15 million berry then he escaped impel down and at the marineford , wg has accepted buggy real danger but buggy come from nowhere ( 15 million berry) . So then even marines thought buggy made these two monster as a subordinates.
So there is one conclusion. Mihawks had already high bounty no doubt and he was accepted real danger no doubt. But of course cross guild has increased his bounty . may be 100 million berry may be 200 million berry idk. But cross guild has so many pirates not just three person. Dont forget that. Luffy accepted yonkou because marine accept luffy has 5600 pirates like the other yonkou crews.
Each warlord was pirate before joining warlord system. ( okay ? )
When warlord system has been broken , all of them have their indivual bounty. ( what we know that , because jimbei got 438 and crocodile has 100m before.)
Now.
Think about jimbei and crocodile case. Jimbei bounty hit 1.1 . Do you think this bounty was given for just beating who is who. Or jimbei bounty hit these range beacuse of he is known yonkou crew member anymore ?
Crocodile hit 1.9 billion berry. Do you think he got this bounty only sinking marine ships ?
Of course he got this bounty for creating dangerous thing.
Buggy had 15 million berry then he escaped impel down and at the marineford , wg has accepted buggy real danger but buggy come from nowhere ( 15 million berry) . So then even marines thought buggy made these two monster as a subordinates.
So there is one conclusion. Mihawks had already high bounty no doubt and he was accepted real danger no doubt. But of course cross guild has increased his bounty . may be 100 million berry may be 200 million berry idk. But cross guild has so many pirates not just three person. Dont forget that. Luffy accepted yonkou because marine accept luffy has 5600 pirates like the other yonkou crews.
Luffy became a full Yonko after this arc.