Is This Truly Glorious Purpose?

Except, it is all pointless. We learn that there is no way to account for the endless expansion of the branches, and the Temporal Loom was never going to be able to keep it all together. It was always destined to fail. What’s worse, the Loom was always just a failsafe device meant only to preserve the Sacred Timeline in a moment like this — not to save the other branches. Without the Loom, there would be an endless war on every branch and nothing could survive. The only way to make sure at least one timeline survives is for Loki to go back and kill Sylvie before she kills He Who Remains at the end of season 1.
Rather than keep trying to save the timelines by repairing the loom or kill the person he loves, Loki uses his status as a god with superpowers to take the place of Victor Timely and steeps onto the platform himself. He faces the temporal radiation and reaches the Loom, but instead of fixing it, he destroys it. He isn’t capable of taking away his friends’ free will, or of killing Sylvie, but he can sacrifice himself for the greater good and truly achieve glorious purpose.
The God of mischief grabs all the time branches and opens a tear in the fabric of spacetime that leads to the ruins of He Who Remains’ Citadel at the End of Time. There, Loki finally takes what he always wanted, the throne (which turns gold for some season). He turns the dying branches back to life, forming not the linear loom, but Yggdrasil, the tree of life.