It's not that they got nerfed it's more the fact that Karma or the Otsusuki really are raw power since they can absorb chakra and jutsus. Basically, if we think about it as just taijutsu, Lee might play a huge roll in the future of the anime. Naruto and Sasuke relly much more on their jutsu arcenal than him.
theres no way the main antagonsit gon die this early on, naruto or sasuke going out and I don't see sasuke going out as he hasn't passed his eyes on yet which is the only way for sarada to get op asf. personally I feel like narutos boutta die... ion wanna see it happen but plot advancement is plot.