It's hard not to be cynical about the proliferation of "new" national cinema movements: New Argentine Cinema, Russian New Wave, Iranian New Wave, New Serbian Cinema, New Arab Cinema, New Mexican Cinema, and so on. These terms range in their application and stature, and the historical period they designate varies. But they have in common a sense of neologism, of creating an entity out of disparate works through the naming process. This can come from the filmmakers, in manifesto-like fashion, or (more likely) from journalists and critics.
They also have in common in being distinguished from the new waves of the 1960s and 70s. Those waves were hardly a singular phenomenon but they were a connected group of movements. And in comparison, the new "new" waves seem less coherent and more neologistic. And the naming seems aspirational to the prior 60s/70s moment.
I would argue (and maybe others already have) there's something substantial going on behind the rhetorical effect of the "new." What we have is a confluence of a few trends: increased self-consciousness about cinema history aided by national film schools; lowered filmmaking costs so that robust film production is within the grasp of nations formally unable to support much; and the spread of national film policy to nations who for economic and political reasons did not participate as fully in film production before, say, the year 2000. Existing networks of television coproduction and film festival circuits have expanded and have aided the foment of new national cinema movements.
So maybe what's happened is that the industrial conditions have reached a tipping point for these "new waves" while there's been a series of aesthetic directions that, while hardly unified, have given an invigorated form to the industrial trends and to a series of nation-state conditions in a post-Communist-state and globalizing era. A sweeping view, I admit, but I do find the Stephen Crofts' model persuasive from a certain vantage.
Or to put it in a less abstract way: there seem to be a number of national contexts for whom the frisson of realist/contemplative art cinema depictions go hand in hand at a self-examination of national identity in a transitioning time. Think of Romania as a good example. These films get marketed in a superficial way (festivals, critics, etc) as "new" but at their core the films are grappling with a new reality.