How? How would fingerprinting use this? It's formed by data used in the past 7 days and the bigger the space of FLoCs the more likely it is that it changes frequently, for example every day if not more frequently.

The fingerprinting would fail to recover the same code at least once a day unless you always visit the exact same sites every day and never visit a new one.

fingerprinting needs a stable state from the browser to work, not something that changes arbitrarily.