It's inevitable that the history of Best Picture Oscar winners has been fraught. After all, the experience of movie watching is highly subjective - who's to say which picture is really the best of the best.
There have been loads of winners that celebrate movies, including 'Argo', 'The Artist' and, arguably, last year's 'The Shape of Water'.
'Moonlight' is among the most famous winners - and people still sometimes forget it beat 'La La Land'.
Oddly enough there have been some movies led by the same actor(s) consecutively. Examples include 'Birdman' and 'Spotlight' (Michael Keaton) and 'A Beautiful Mind' and 'Gladiator' (Russell Crowe).
Some many still believed were undeserved winners, like 'Crash'. Others have aged horribly *cough* 'Driving Miss Daisy' *cough*
In any case, you can't deny that they capture a moment in time. Each also propelled the movie industry forward in their own distinct way.