Nico was in fresh air the whole race, Hamilton was tucked up behind his wing, Hamilton would have had noticeably higher air temps cooling his entire car, from brakes to engine. Considering the problems both were having that is quite clearly the main difference, it also wouldn't have helped that the team did another crappy and slower pitstop, the extra half a second or whatever it was with no brake cooling what were already hotter brakes, to blame Hamilton for that is nuts.
If we want to get into the blame game, what about Nico's clear and obvious cheating, both in being the first to attempt to use higher engine settings(he did it in race two afaik, Hamilton used it to defend in race 3), he clear as day messed up in Monaco... even if just on the slightest fraction of a percent chance that the lock up was unintentional the reversing towards the track ruining Hamilton's lap was VERY intentional(realistically both were intentional). He also basically ran Hamilton off the road in the first corner in Canada and cheated by cutting the chicane to give himself a gap receiving no penalty.
Consider that since then we've had a couple dozen, maybe more, laps wiped off in qualifying for gaining an advantage by leaving the track... he did the fastest lap of the race at the time and pulled out a large advantage that went completely unpunished.