no where in there do I see or feel anything about growing past the need for his lightsaber and I can’t make any sense of that in context to the scene. It’s not like he thinks upon defeating Vader that he’s ascended to a higher level and could fight the Emp without his saber
He realizes that fighting isn’t the way. If it costs him his life, so be it, but he’s trusting the Force now and not himself. That’s the “leveling up”.
Like many elements of ROTJ, it’s murky and not perfect and not everyone will agree, but that’s my take:
He either tosses it because he’s just ‘moved past it’ so to speak, or he’s just being stupid. 😉
JEDIT- Also, isn’t it maybe more interesting to leave it a bit ambiguous by not seeing the saber on his belt at the end? I dunno.
It’ll be interesting to see if he has it in the ST.