One of my favorite aspects of this movie is that they break out of the time loop through science instead of some form of objective morality. There is no lesson because there is no higher being. We are alone. Sometimes bizarre anomalies occur. That's it.
OK, seen it. Find the breaking out through science to be incredibly suspect. Since you're dealing with theoretical physics on a level no one has ever experienced and an amateur scientist at best is breaking them out, the fact that it works the way it does is hard to swallow. Outside of some of the more forced SNL-level goofiness (and to me "SNL" has a very negative connotations), that is probably the worst part of the movie.
I do agree with the no higher being, we're alone, gotta figure out own shit out and make this planet decent as can be. I actually really liked the film. I think it falls into too many romcom tropes and isn't remarkable enough in its cinematography for it to be anything beyond max-very good, but I was into it, beginning to end.
Like FLY said, I do like that it starts out well into Nyles' loop, and the manner in which key points are revealed is masterful. I think Andy Samberg actually acquits himself quite well and Milioti's performance is good, but kind of a lay-up considering she's the conscientious, smart, however flawed female character that's meant to be admired. I like Simmons a lot here. The scene where we meet his family is a defining scene of the film for me. That, and...dinosaurs. He's far from a favorite all-time actor and I don't get why he's got a Best of Decade nomination for the rather simple, one note, intense, intense, INTENSE role in the meh Whiplash, but he has an excellent turn as a supporting actor here.