The first meaning is DESCRIPTIVE, and defined in terms of statistics. Here, normalcy is a matter of empirically quantified FACT.
The second meaning is NORMATIVE (sic), and has absolutely nothing to do with statistics. The second meaning refers to the formal and informal empirical markers which signify a population's PREFERENCE.
Now, aggregate PREFERENCE is always decided by aggregate POWER, and so here normalcy is a matter of opinion, presented via power as fact. Thus, politics clutters culture, and thus both culture and politics draw the attention, of both political scientists and anthropologists. Yes, yes, all the other social science disciplines as well ... vis-a-vis intersectionalism/ty.
So, the next time you hear junior epistemologists babbling about neuroDIVERGEnce or criminal abnormality do review their statements, in case these two senses of normalcy are clumsily mixed up.