'Roughening Up Fantasyland', a panel at Eastercon, discussed the introduction of elements of realism into genre fantasy novels. Joe Abercombie, Tanith Lee, Mike Cobley, Maura McHugh and Holly Black debated the various ways that modern fantasy authors are moving beyond the cosiness of genre conventions, the bundle of tropes satirised in Diana Wynne Jones Tough Guide to Fantasyland (eg 'Hovels are small squalid dwellings, either in a VILLAGE or occasionally up a MOUNTAIN, and probably most resemble huts. The people who live in hovels are evidently rather lazy and not very good with their hands, since in no cases have any repairs ever been done to these buildings (tumbledown, rotting thatch, etc.) and there is no such thing as a clean Hovel. Indoors, the occupants eke out a wretched existence, which you can see they would, given the draughts, smoke and general lack of house-cleaning...') Abercrombie's stuff is a good example of the realistic turn - stories where people can hurt and die, using real swear words in the process.
As I recall through the distorting mists of beer and time, here was some dissent from the audience - along the lines of 'isn't fantasy meant to be escapist?' It certainly presents itself as such - I remember all those Conan forewords, inviting the reader to pull on boots and enter a world where villains were evil, women beautiful (etc.) And, just a few weeks after the panel finished, I've thought of something to say: that realism (or perhaps authenticity) is necessary for fantasy to work as escapist literature: an integral component, rather than an invasive element.
Part of my point is that much fiction, not just fantasy, has a world-building element and an escapist function. For instance, I've just finished a (really good) mundane novel: Engleby, by Sebastian Faulks. The novel includes various milieux, atmospherically described: a boarding school, Cambridge in the 70s, London in the 80s, an asylum. I would not wish to be in any of these settings as experienced by the protagonist, adrift in misery and violence. But one reason I enjoyed the book (and chose to read it on trains and after work, as relaxation and pleasure) was the process of being transported to a coherent, believable world - the novel provided escape, as well as insight and poetry. Another example: Exhumus describes the strange attractiveness of an extreme fictional/historical setting in his thoughful post Bookish bereavements - fiction done well seems to offer us a home from home, however bizarre and challenging that home might be.
So I see the escapist bit as being part of the pleasure of any literature, dependent in part on believability - which is where the realism comes in. Jarring elements break the dream, and clichés, outworn tropes and simplistic characters or plots are jarring elements. So maybe fantasy has to be toughened up in order to work at all. In a way, imaginary world fantasy has to work harder to create an escapist setting than realistic fiction - as it has to include made up elements, but still provide a seamless setting. Credible reference points are therefore vital, and recognisable behaviour and language are part of this.
That isn't to say that fantasy novels should become versions of Last Exit to Brooklyn with magic swords, or that works in the classic mould are somehow irrelevant. Authors like Tolkein, Peake, Cabell, Eddison and Dunsany were individual stylists working without precedent: their authenticity comes from the truth to their own vision, their unassailable brilliance at using their own language. However many modern writers are working in a genre, a shared world almost as tightly defined as the 'West' of Westerns; a market with definable reader expectations. The readership wants to have its cake and eat it: genre work with familiar elements, but with freshness, relevance and depth of character comparable with any literature. Luckily authors such as the panel members are up for the challenge.