That’s the view of former F1 driver Pedro de la Rosa, who has seen Hamilton waltz to his fifth championship.
Vettel has been Hamilton’s closest challenger throughout the season but the Brit wrapped up the title in Mexico last weekend with two races to spare.
Vettel crashed in Germany earlier in the campaign, while he also struggled in China.
Hamilton and the German also collided at Monza, leaving Vettel spinning, while Hamilton went on to win the race.
And De la Rosa believes Vettel’s team should have given him more support during the tough moments of the season.
“Ferrari have had a car at Mercedes’ level in every way for the first time in the hybrid era,” de la Rosa told Spain’s El Confidencial.
“But Vettel’s mistakes coupled with the fact that Ferrari did not protect him meant that they lost the world championship.
“In the life of a driver, when you make a mistake, but particularly when you’re at Ferrari, the team has to protect you.
“If it does not, it’s very difficult for the driver to handle the pressure generated by his own mistake.
“I remember when he crashed in Germany, it was a very strong blow to Vettel with a very prominent error. But I didn’t see a very strong defence of the driver. I didn’t see it.
“Then came Monza, when Hamilton overtook him dramatically and won the race.
“I think that given the pressure Vettel was suffering, I would have expected more public support from the team.
“Maybe he had it internally, but it should have been public to relieve the pressure, especially from the Italian press. At times like those, it’s harder to win with Ferrari.
“When it starts to go wrong, it’s very hard to have concentration and a cool head at Ferrari.”
The next F1 race comes next weekend in Brazil.
The season finishes on November 25 in Abu Dhabi.