I know that at the heart of this belief is that the mortal life is much less important than the soul or afterlife
Yes. THAT is the core. A belief that our "Souls" are immortal and will spend SOMEWHERE (Heaven or Hell) for all time.
It is not the get out of jail free card that some people try to portray it as From a religious perspective salvation is a miracle that must be available to all that claim it
And if true than "false salvation" would never happen
The stripes of a tiger don't wash away.
Be a man of steel not clay
JYD #102