Davis commentary I agree with

The Coens have given us a melancholic, sometimes cruel, often hilarious counterfactual version of music history. It’s a what-if imagining of a cultural also-ran that maybe tells us more about the truth than the facts themselves ever could. (Time Out London)
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 "Inside Llewyn Davis" isn't about someone trying to make it big, but someone just trying to make it, and the Coens celebrate the hard road that can inspire great art. (Playlist)
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Above all, “Inside Llewyn Davis” is a revelatory showcase for Isaac, who sings with an angelic voice and turns a potentially unlikable character into a consistently relatable, unmistakably human presence — a reminder that humility and genius rarely make for comfortable bedfellows. (Variety)