Ross Douthat on cynicism in NYT:

"But like all cynics I prefer to call it realism. If you want Trump gone, the existing case for impeachment will not do it. You must either prove him — not Stone or some other hanger-on, but him — guilty of conspiracy, or accept that he will depart only when he is beaten at the polls."

Read the article here.

Trump aside, the difference between realism and cynicism is the amount of pleasure and nastiness with which the realist announces his "realism". A realist can still be unhappy about reality.
A true cynic always preaches cynicism. Having said this: the case for impeachment is also a case against actual existing democracy.