Why Forbidden?
To sin is to self harm. The cost is greater than the pleasure, though the deception in that moment is to believe it probably won't cost you what it actually does.
We love sin, but it doesn't love us back. As you saw, it brings death.
"For the payoff of sin is death, but the gift of God is eternal life in Christ Jesus our Lord." Romans 6:23
"Every good thing given and every perfect gift is from above, coming down from the Father of lights, with whom there is no variation or shifting shadow." James 1:17
So, if we want something that is forbidden by God, it is not the good thing we think it is
because he IS the giver of good things!
If it's not from him, therefore, it's not good. It's bait.
Rest on this promise from Psalm 84:11:
If it's not yet, it will be. For those who are in Christ, we endure for the fulfillment of God's promises and the joy that will be. You can count on it.