“I’m as shocked as you are that I’m here,” Nate Bargatze told the audience during his first Saturday Night Live monologue last November. At the time, the host’s lightly self-deprecating banter was probably accurate. Bargatze is a seasoned standup veteran who’s played increasingly larger venues since he began popping up in the mid-2010s, and yet he’s never had a starring sitcom or movie role for the standup-agnostic masses to digest. (His only acting credit so far is from a 2014 episode of Maron.) Still...