CAMRA are indeed all about 'real', cask ale. But the organisation was created to fight against the encroaching lagerisation of everything. In the 70s and 80s (from what I can tell, I didn't pass legal drinking age until 1996) the beer scene in the UK was dire. Mass produced lagers were about the only thing on offer, the likes of Carling, Fosters, Stella etc. You'd usually find there was a 'bitter' on tap in most pubs, but it would be a bland, mass produced brown beer like John Smiths or Tetleys. Even in the early 00s many pubs had a bunch of lagers and a concession to other beer types in the form of a single tap of fullers "London Pride". The traditional breweries were suffering and the real art to beer making was being lost in the UK, despite our rich history of it.
At the same time, supermarket sales and home drinking were impacting on the pub, which had been a traditional social hub for a lot of the country for a long time.
So in stepped CAMRA to promote real pubs and real British beer, with real, varying flavours and an eye to tradition. It was a roaring success, though slow-burning at first. Now they hold massive festivals, local real ale breweries are everywhere, pubs have a wide selection of great stuff again.
The craft revolution some years later took them by surprise. Their attitude to good beer in a keg seems to be "well it's not exactly what we're about, but great! People are taking an interest!". AFAICT they've decided the cask is their focus, but so long as we're not going back to the days of five lagers and a substandard 'bitter' on tap in every pub you go to, then we're all good.