how is graves op?

He can't hit through minions You can walk out of his Q's 2nd trigger which is its primary damage His range is low

I think maybe in higher elo, where ADC mains are actually ADC mains and Support mains are actually Support mains, he gets punished in lane. Perhaps strong in comps that have good engage which lets him back it up with his in your face kit, but I doubt he can do much vs poke + disengage + sustain comps. He can't hard engage like Ashe, he can't provide poke like Ezreal, provide chase potential like Sivir, or take down turrets as fast as Jinx, Trist, and Cait. What he can do is probably more easily punish lower ELO players better than many other ADCs.

I mean I'm watching Dyrus stream right now and the graves is still dominating lane in the high elo though teamfight wise he's extremely easy to get to

Well he's a great pick vs. a lot of melee comps. Because of his new passive, his bullets stack in damage if they hit the same target.

jinx is weaker now than before, or rather, she's more or less as strong as before but now there are stronger champs.

now there is graves and missfortune. graves because his damage potential is very scary, and he's harder to pick because of his natural tankiness. miss fortune because her new scaling on her ult lets her hugely benefit from a lead or a good team comp, that jinx lost whith her attack speed loss on rockets.