Perez is just more efficient than Kamui, no coincidence. He has scored almost twice as many points as Kamui and had his share of bad luck too. It's Perez who makes the strategy works. There were too many times that it has happened the same. If I would be a team boss, I would take Perez over Kobayashi on any occasion.
Perez is amazing. I'm not contesting that point at all.
True that both had some bad luck, also they both made their share of mistakes each, but Perez had luck (luck that nothing went against him in races where he had better strategy) whereas Kamui NEVER had such luck that is a fact which pretty much everyone miss.
his rear wing flap was damaged at T1 of opening lap and was flipfloping for whole race
his rear damper was slowly failing from in the middle of FP3. Team could identify the problem only because he kept insisting sth was defo wrong with rear suspension for several hours after Quali.
In the race, he asked for wet tyres on lap 3 or so but team ordered him to stay out (eventually pitting lap 9 or so). When it was drying up, he asked for dry tyres earlier but again team ordered him to stay out. Eventually his brake failed and had to retire.
good quali. But during support race on sunday morning, a car put oil patch exactly on his starting position, which hindered his start apparently.
his Q2 best lap was set with right rear tyre (iirc) being sprayed with leaking oil from his car. Without which he wouldve started from better position and might have finished higher.
taken off at St devote several sec after the start. Also, he insisted different tyre choice for Quali than team's recommendation. and it turns out that his choice seemed to be correct.
stuck behind Kimi and di Resta for long time at critical point of the race, which cost him 15sec at minimum. Plus team changed strategy from 2 stopper to 1 stopper in the middle of the race. SS>S 1 stopper was the strategy that was meant to fail in the first place. Plus, before the race, he insisted 1 stopper strongly, same as his teammate's, but the team denied it.
also the team gave slow 1st pitstop at Valencia, 1st corner incident at Spa, etc
Besides above, he had minor bad lucks here and there, like slow pitstop (like 8sec instead of 5), questioning strategic call (earlier than planned pitstop despite his good pace), all resulted in lost position and time at critical timing.
Also races like Barcelona and Germany, he had to stuck behind slower car for many laps despite having pace and good strategy. Kamui just is without luck, almost miracle-esque.