Yes, I was slightly baffled by the reference to Lean, whose career was entirely typical of a British filmmaker at that time - he got a low-level studio job in 1928 (as a clapper boy, in his case) and worked his way up, becoming arguably the best editor in British cinema in the 1930s before turning director in 1942.
This was such a common way into the industry that it was completely unexceptional (Alfred Hitchcock started out as a title designer and broke into directing via the art department and the odd bit of screenwriting) - and it remained the best way of breaking in decades later: Nicolas Roeg was born the year that Lean got his first industry job, and he's another one who started out as a tea boy and worked his way up (via outstanding cinematographer, in his case).
In any case, the comment that they were "not educated in film before they entered the field" is flat-out bizarre. Regardless of what knowledge they may have picked up beforehand, surely their lengthy industry apprenticeships before they were allowed to direct their first films constituted the kind of hands-on education that's worth any number of film-studies diplomas? And surely this is exactly the kind of film training that's impossible to get in countries that don't have established film industries? (It's precious hard to get in many countries that do, thanks to the fragmentation over the last few decades!)
Anyway, just to get back on topic, here's Jonathan Romney's
Cannes overview and
individual film round-up - he liked the Sorrentino and the Ceylan more than many.