Indeed I'd say this "vanguard of postcapitalism" description, and the "open source" tag, is more a Guardian invented exaggeration. Many craft breweries have homebrew roots and, generally speaking, many of them are pretty accommodating of homebrewer inquiries to various degree.

Brewdog's the first one I've seen that's opened up all of this at once, but it is not uncommon (at least in the US) for an American craft brewery to, say, publish a "clone recipe" of one or many of their beers in a homebrew magazine.