If death and suffering entered the world after adam and eve ate--according to your myth?

Then they were immortal before they ate correct? Then why the big hullaboo in genesis about the tree of life (and later protecting it). Why would there be a tree that gave immortality when according to your book adam and eve and the creatures already had that. Sorta useless shrub wasn't it--or was the story put together by people who were scared of death and a tree of life is a great selling point--and screw logic lol.