Not sure TFA supports your assertion that he was a socialist.
The principles for Neals Yard regarding worker involvement, favouring encouraging and supporting workers expanding businesses by starting their own offshoots, and his practice of giving away businesses does smell lightly of something close-ish to socialism, though perhaps closer to the kind of Owens and Fourier, that Marx came to describe as "utopian" for their failure to provide any answers for society-wide structural change, than any more modern version.
As another comments pointed out, this article is peak Guardian - favouring small businesses and artisanal products over mass production, and countering extremes of capitalism in eccentric small scale ways, while at no point favouring anything to effect actual lasting change in any way that might threaten anyone with money.