It fits with the whole student surpassing the master trope. With his new form, I think Naruto could definitely give Iruka a run for his money in an all-out fight, though I'm not sure if he could win. Iruka's no pushover and has experience on his side. It's been long enough however that I think Naruto has finally grown to become a slightly better ninja than Iruka. Who's the bigger monster here at this point in time?