But this doesn't mean that seconds* used to be smaller, does it?

If we think that expansion is only measurable at the larger scales and only measurably affects distances outside of gravity-bound systems and not within them, does that mean that time moves very differently in the voids between the superclusters to how it does within them?


*the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom