I guess the lesson here is that <Space x Time> is always a constant!
A B-Tree is already scalable, fast, and doesn't require 128x more work for a single query. THAT is your competition here, not some "fixed amount of processing". Kangaroo et all can run concurrently on an unlimited number of computing devices, and use the one and same central DB. Which may not even need to be large at all, only adding a few DPs every now and then. However, those special values represent trillions of EC operations EACH.
Faster = Larger
Slower = Smaller
The B-tree is not a competitor here; the additional processing has nothing to do with the search speed in the database, which is fast enough. This is a different issue. As for Kangaroo, its problem is that it is probabilistic, and as the search space expands, its success rate deteriorates. You know very well that adding DPS doesn’t work like magic.