Board Thread:Questions and Answers/@comment-35878647-20191103033103/@comment-29325824-20191103083843

Yes. To clarify, Ichigo's unique hybrid nature and immense power made him a perfect candidate to replace the old Soul King as the Linchpin after Yhwach killed him.

Ichibe fully intended to do so (and Shunsui was even aware of it), but after Yhwach absorbed the old SK's powers, he became another potential candidate. So when Ichigo killed Yhwach, Ichibe was able to turn the latter's corpse into the new Linchpin, thereby sustaining the worlds.

This was actually forshadowed in the manga itself, with Shunsui giving the Soul Tickets to Ichigo's friends, and Ichibe apparently sending Ichigo to his death against Yhwach.