The next world is about traveling to God. To understand how that is possible when God transcends his creation, you have to understand the role of the connectors to God. The path to God is Unseen in this world, the sign/proof Mohammad (s) and Ali (a) are is unseen, but the unseen becomes vividly seen in the next world. The connection of each Ahlulbayt (a) from sky to lowest earth, is always been a thing from Adam (a) to the Mahdi (a). "peace be upon you o light of those stuck in the darkness", even in the darkness, the Imam is there with every soul, no matter how misguided. But he won't force the sign and connection of the sky because its harmful to souls that are misguided to do so.
Everything is a set up to return to God and be guided to God.
If material pleasures was the goal, the trial of this world, trial of Angels with regards to Adam, all would be purposeless.
There was no need to reward or punish, all would be created in paradise, and this world would not have come to be.
But the fact is, the next world is closed by the nature of what it is, from those who journeyed away from God and died hating his light. They can't benefit from its water even if God wanted to, its forbidden upon them by nature of what it is and what they've become.
The Quran is trying to make us perceive the next world to some degree with spiritual vision in this world. But people hate the idea of God punishing them, take it personally, and turn away from his guidance as a result.
