lol when did he spam big techniques? Shadow clones? Although he has been fighting for like the start of this war with roughly 3-4 recharges.
Edit:
OT: Kagaya's dimension technique uses a lot of chakra, as you saw Sakura's 3 years worth of chakra could do roughly 2-4 dimensions, while Kagaya is just spamming the dimension ability. So it's not the fact that Naruto has more chakra, but that Kagaya is using more chakra than Naruto who is mainly using taijutsu.