Psalm 91:16 With long life I will satisfy him, And show him My salvation.”
Long life and Salvation are two different things; you live longer in the land of the living and Salvation is eternal though it begins here in the temporal, with us accepting Jesus Christ.
This Psalm was written before Jesus Christ walked on the earth. There was no salvation for the soul at that time, but if you dwell in the secret place of the Most High, then you shall abide under the shadow of the Almighty.
If you had a covenant with El Shaddai, then you had Shalom, then this Psalm was applicable to you then, and to us now.
The range, because of it being spiritual and natural, has to be specific in its application, or it will at best be good words in a book, but meaningless.