BEFORE Adam gave in to his Temptation, and enticement from satan, there was no "God's Wrath" to deserve. and then Adam fell short of God's glory, and GRACE (unmerited favor) kicked in when God didn't JUDGE ADAM on the spot, and eradicate him. Adam was never CURSED, and his human nature never changed.
Yet we, by way of Adam's sin, are by nature deserving of God's wrath until we repent and believe.
That really looks to me like Adam's nature changed. He started out good, and then was not. And he knew it.
By nature deserving of wrath are the words Scripture uses