Muse, muse muse. Sing in me Muse, and through me tell the story of that man skilled in all ways of contending,
see, the Coen brothers are very baity and you should take that into account when you review .. a review. Obviously no paid reviewer is going to stick his neck out and say "Oh Brother" because they would get fired for having an opinion. It's kinda like when you read the Rolling Stone's Top 100 Whatevers, it's not what's actually good that goes in it, it's what's dictated commercially. The Coens aren't really a money-making machine but they have garnered praise as artistic filmmakers so obviously the reviewers are going to make the list in "most-artsy" order.
No Country is by far the most well received in the filmmakers circles. Barton Fink is the most beloved by theater critics. Fargo is the one that put them on the map, True Grit the one that made the most mony, so fashion/lifestyles magazines would put it at N.1, and obviously the most popular among normal people is BY FAR The Big Lebowsky, so any non-Coen fans would rate this as their favorite.
And it goes to show, from the very links you have posted, that there are substantial discrepancies in those lists. Studiobinder (?) has A Serious Man at N3, And Inside llewyn Davis aty N11, while the tomatometer has Llewyn at N5 and Serious Man at 10. That's a big swing.
Goldderby (??) has Oh Brother over Lleywn, but does not have No Country at N1.
Screenrant has Fargo at N1 and Serious Man at N5. The Guardian - *very* reputable when it comes to reviews - has Fargo at N5, and Big Lebowski at N2, under No Country.
I guess this wasnt a convenient review to link.
Trillist has Fargo at N1, and then they have .. Raising Arizona at N2, Millers Crossing at N3, No Country N4, and the Hudsucker Proxy, which most others above put in the low 10s.
Theringer has A Serious Man at N1 !!, Lebowski at N2, and Fargo is under Miller's Crossing.
And Indiewire has No Country, Llewyn, Fargo, and Big Lebowski.
.. all these reviewers have their own frame of reference. The reason why it seems that they cannot agree on a proper ranking is that they are doing a job, they cater to their readers and the readers of Indiewire are not the same readers as The Guardian.
I don't.
I can tell you that all of my dumb friends (and some non-dumb ones) love Lebowski and hate Barton Fink, if that is any consolation. You can help yourself to a dozen youtube rants on why Barton Fink is a masterpiece, and yet when we went to the theater everyone hated it (me included, i must be dumb).
Fargo is a comedy of errors. No, not the Shakespeare play, but the term that means "a story that progresses because the characters involved are incompetent". I don't like that. I don't think that's the peak of screenplay writing, and while Fargo is a good film, it's not what i would consider a masterpiece. I mean, neither is The Hudsucker Proxy, but i'd rather re-watch that.
The Big Lebowski is both the funniest in your classical sense, and the most easily-digestible. I get that many people love it but i think the characters tend to stick out too much from the frame. Let's say that Jesus Quintana is a less believable character than Big Dan Teague.
Now .. Oh Brother, that's a masterpiece.
True Grit is what happens when the Coens decide to make some money. They did a straight western and everyone paid to see it. (also the little girl was brilliant)
Old Country is .. difficult. It's less hermetic than Barton Fink, but also contains many touches of elegance when it comes to scriptwriting, most of which went above my head because i'm not the target audience for that kind of material. Like i said, i'm dumb.
I like - as you would know - films that sit you down, and then in a clear voice say "I AM GOING TO TELL YOU A STORY" and then do.
Obviously at this point i have to say, "to me". To me Oh Brother is a masterpiece. The script flows flawlessly, punctuated by amazing performances by literally everyone involved. Even the 5 f* seconds of screentime the record shop seller has, the 30 seconds of the pomade seller, the sets, the songs, the audio, photography. I love this film so much i fuck it.
I'm not sure what Fargo has that you love it so much.