A number of reasons for protests and other post-election hysteria (the more obvious emergence of an Alt-Left that has always existed-- as opposed to the Alt-Right that got more play during the campaign...How large is each?)
a.) Our youngest citizen/voters have little/no context for an election that was so strange and had such regrettable candidates.
b.) Younger but slighter older citizens/voters have no memory of a Dem losing (go back to 2004) or a GOPer winning-- and don't know how to respond well.
c.) Again, moreso among younger folks in their generation: an increased tendency toward sensitivity and taking disagreements personally.
d.) Again, moreso among younger folks and more prominent among self-styled liberals: the (often-vital) importance of gender politics-- and therefore both the value of a Clinton presidency because she was a woman and an increased subjective level of harm felt from Trump's comments.
e.) Particularly among self-styled liberals, a higher value on words-- and thus, finding Trump's rhetoric (vs. the reality of the moderate way in which he will govern) more troubling.
f.) Personal values/ethics often led to downplaying Trump's flaws or mostly ignoring Clinton's. From there, lack of empathy (particularly on the Left; see: Haidt?) made it difficult for NeverTrumpers, NeverClintons, and Neithers to understand each other.
g) Certainly, values and (often rational) ignorance are in play. But in biblical terms, we can mix in idolatry as well.