I think you underestimate how much of a speedup we're talking about: it can pull in the entire filesystem in a couple seconds on a multi TB volume with Bs of fi

I think you underestimate how much of a speedup we're talking about: it can pull in the entire filesystem in a couple seconds on a multi TB volume with Bs of files. I have yet to see anything in the linux world (including the OP) that comes anywhere near this performance level via tree walking.