Sort of in the sense of human minds being more like fixed black boxes that one might like to think. What's Knightian free will, though?
Knightian uncertainty is uncertainty where probabilities can't even be applied. I'm not convinced it exists. Some people seem to think free will is rescued by it; that the human mind could be unpredictable even in theory, and this somehow means it's "you" "making choices". This seems like deep confusion to me, and so I'm probably not expressing their position correctly.
Reductionism could be consistent with that, though, if you explained the mind's workings in terms of the simplest Knightian atomic thingies you could.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.