His verse was said in the spirit of competition. He wasn't saying he would ACTUALLY murder them, he was talking about doing better than them and trying to be the best of the best.
Sean being a man and respecting what K dot put down on the mic, like kendrick said I got love for all you but im trying to murder all you. We all know kendrick is the alpha over all 11 of those rappers of his generation.
He has more drive and want to make the OG’s proud! It’s their culture of music and talent that should be preserved in its natural form as much as possible. Part of that world is where intellects get to exhibit their craft in rap battles.