remember the word of the great sage "the sage mode is not just meant for anybody its because its Naruto snd jiriya"I think so, After all he did invent Rasengan
jiraiya never mastered sage mode soo naruto is the only one who mastered itremember the word of the great sage "the sage mode is not just meant for anybody its because its Naruto snd jiriya"
or wat tsunade said
jiriya was the only one in the village to master the sage mode
not just anybody could learn sage modeI don't think it's got to do with chakra, anyone can master it after all you absorb chakra.
The process is very risky so no one attempts at it, you could die.
You also have to go to Mount Myoboku and no human actually goes there. Jiraiya stumbled there by accident, Naruto's case was an emergency and also they believed he was the child of prophecy.