The philosophy of this movie means more as you grow older

Blade Runner symbolizes the desperate lurch between life and death and how we fight to hang on to what makes our personal existence unique.
The character of Roy Batty is fascinating because he has real memories from the short life he's lived, although he knows he's a replicant. Compare him to Rachel, a replicant who did not know she was a replicant, with few life experiences and childhood memories that aren't hers. They come at the question of "what is my life?" from completely different perspectives.
In the end, Roy Batty choses not to kill Deckard and to die with having someone know that he existed and did something noble at the end. Rachel, realizing she has no home and will be hunted, leaves with Deckard to try and have a life of experience.
Blade Runner is a visually beautiful movie to look at but what makes it special is the narrative it creates about the struggle for meaning between the life we live and the inevitable death that follows.
Those who criticize the movie should watch again and think on what I've shared. I saw this movie in the 80's when I was a teenager. Now I'm 52 and it means a lot more now than it did back then. Experience. Memories. A truly rich life needs both for anything to have meaning.