It's probabilistic, like everything, but N-95 masks do protect the wearer from particles that small. The CDC purposefully lied to you so that you wouldn't stockpile masks they (understandably) wanted to use elsewhere.
/https://www.semanticscholar.org/paper/Filtration-Performance...
>Consistent with single-fiber filtration theory, N95 and P100 respirators challenged with silver monodisperse particles showed a decrease in percentage penetration with a decrease in particle diameter down to 4 nm.