Spelljammer Is Shatterspace the 5e equivalent of the Astromundi Cluster?

[Matt Adler]

I'm reading the Spelljammer novel Memory's Wake, and I'm wondering: is "Shatterspace" the 5e equivalent of the Astromundi Cluster/Clusterspace? If not, the concepts seem really similar. I wonder if there's more to it than "We think this name sounds better." I'm guessing the whole Worldbreaker mythos was something added just for this novel.