Of course I don't believe the Adam and Eve story to be more than a myth, but just supposing it was true, what on earth did the pair do wrong? They used their God given intelligence to find out more about the world around them, good for them. If God had wanted obedient puppets then he shouldn't have created them with curiousity! For God to chuck them out of Eden, and cursing humanity forever was OTT, and then some! When my grandsons have a temper tantrum I put them on the 'naughty stair', maybe God's mum should have done the same with him!!!
I would agree with you if God didn't warn them about it clearly.
[19] "O Adam! dwell thou and thy wife in the Garden, and enjoy (its good things) as ye wish: but approach not this tree, or ye run into harm and transgression."
[20] Then began Satan to whisper suggestions to them, in order to reveal to them their shame that was hidden from them (before): he said: "Your Lord only forbade you this tree, lest ye should become angels or such beings as live forever."
[21] And he swore to them both, that he was their sincere adviser.
[22] So by deceit he brought about their fall: when they tasted of the tree, their shame became manifest to them, and they began to sew together the leaves of the Garden over their bodies. And their Lord called unto them: "Did I not forbid you that tree, and tell you that Satan was an avowed enemy unto you?"
[23] They said: "Our Lord! we have wronged our own souls: if Thou forgive us not and bestow not upon us Thy Mercy, we shall certainly be lost."
[24] (Allah) said: "Get ye down, with enmity between yourselves. On earth will be your dwelling-place and your means of livelihood for a time."
[25] He said: "Therein shall ye live, and therein shall ye die; but from it shall ye be taken out (at last)."
[26] O ye Children of Adam! We have bestowed raiment upon you to cover your shame, as well as to be an adornment to you. But the raiment of righteousness, that is the best. Such are among the Signs of Allah, that they may receive admonition!
[27] O ye Children of Adam! let not Satan seduce you, in the same manner as he got your parents out of the Garden, stripping them of their raiment, to expose their shame: for he and his tribe watch you from a position where ye cannot see them: We made the Evil Ones friends (only) to those without Faith. (Quran 7:19-27)
Here is the most important part of the story where we can find in another Sura.
[35] We said: "O Adam! Dwell thou and thy wife in the Garden; and eat of the bountiful things therein as (where and when) ye will; but approach not this tree, or ye run into harm and transgression."
[36] Then did Satan make them slip from the (Garden), and get them out of the state (of felicity) in which they had been. We said: "Get ye down, all (ye people), with enmity between yourselves. On earth will be your dwelling place and your means of livelihood for a time."
[37] Then learnt Adam from his Lord words of inspiration, and his Lord turned towards him; for He is Oft-Returning, Most Merciful. (Quran 2:35-37)
He forgave them and there was no need for any curse upon human beings after that.
Any fair and wise human being wouldn't curse and punish the sons and daughters of a pair who did a mistake, how about the One who created those human beings?
Wouldn't he be more forgiving than us, much more wiser than us?
I think there is no question about that.
Peace and blessing,
TT