What are the left over Clusters for?

What are the left over Clusters for?

I've been nearing the end of the story quests, and decided to start
sweeping up the last few sides/activities/collectibles, etc. As part of
that, I've just finished gathering the last Data Cluster. Got the
achievement and everything. Similarly, I've picked up every super power
upgrade I can buy. Got that achievement too.
But, I still have 190 clusters left over. And this seems... strange. There
are a fixed number of clusters, and a fixed number of things to spend them
on, so am I missing something? Is there something else to spend them on?
Or are there just a hundred and ninety more Data Clusters than you need to
pick up?