How do smaller capacitors filter out higher frequencies than larger values?
If practical capacitors were purely capacitive, then indeed, a larger capacitor would do an even better (or at least &quot;as good&quot;) job of filtering high frequencies as a smaller value one.
But capacitors are not purely capacitive; ones we can practically build are also unfortunately inductive, and at some frequency the inductive behavior dominates over the capacitive one, and they are no longer useful as shunt elements for filtering.
It happens that the construction of low-value capacitors puts the point where they become more inductive than capacitive at a higher frequency than the construction of high-value capacitors.
As a result you tend to see low value, low inductance capacitors (ideally in physically small packages) very close to IC pin pairs to handle high frequency needs, and a few higher value capacitors slightly more remote to handle low frequency ones.  In terms of low frequency analysis they are all in parallel, but in terms of AC analysis with the implicit self inductances, only the small local capacitors are meaningfully in-circuit at the highest frequencies.