My interest in this pianist has soared recently, and I just love Alfred Cortot's Chopin playing. It sounds so spontaneous, almost improvised, yet still his interpretations manage to capture the scope and feeling of the work, keeping it all cohesive, despite his manner of pushing and pulling the tempo all the time etc.
I see a lot of comments from people who doesn't like him who say that he uses too much rubato or that Chopin "should" be played in a more restrained, even manner, without big and "too expressive" phrasing. However, after having grown accustomed to Cortot's way of playing I feel that I find more and more modern recordings very sterile and boring, and very samey (can't tell pianists apart), while he has an instantly recognizable personality in his playing. I'm not saying Cortot is the only alternative though, there are a lot of great recordings of the Ballades out there that I love.
But onto the topic, what would happen if more pianists started to play more in his "unconventional" manner? How would critics and audience react to this spontaneous, improvised and sensitive way of playing Chopin? Would the pianist be dismissed as an idiot who forgot to bring his metronome and rejected for not following the "conventional" way of playing Chopin? Would it hurt to return a bit to the manners of his (Cortot's) era of pianism?
I might sound ignorant but I'm just curious 
I like your question, but just on instinct, I reject the notion that those who play freely, or with personality, are ignored these days.
To best answer it, you should ask yourself, who are the highest regarded Chopin players of today, and how is their playing? In other words, start at the top, not at what a teacher said, or what you heard in a masterclass, or what the latest winner of Blah Blah International Competition plays.
I suspect you may find, taking this approach, that performers are not as constrained as you think. We're so bombarded with recordings of the same pieces, it is easy to forget the all those are going to be forgotten, and only the best will stand out.
how many pianists were playing at the time of Cortot? Not as many as today, probably, but a damn lot. History filtered them out, leaving only a few of his generation to stand the test of time.
That said, my personal view of Cortot is a
bon vivant who happened to play piano. He obviously didn't kill himself practicing, and made up for it with a superlatively suave and charming personality (both at the keyboard and away), and with manipulating the technology of the day brilliantly.
I think it was Zimmerman who said he listened to remastered Cortot recordings, only to find that he was faking his way through the entire set of Chopin etudes. But then he realized, that it was part of Cortot's genius, to play to the primitive microphones in such a way that you couldn't tell, and that the thrust of the music was so powerful and clear.
About "returning to manners:" the conventions that spring up in any era are a product of that era. I've heard people advocate breaking the bass note and treble, just because it was done in the past. That is not a sufficient reason. Anything we do for expressive effect has to be able to be understood by the people we are playing to. Just to imitate recordings is really not enough.
Walter Ramsey