I'm going to call this "environmental ambient", a term I may or may not have just invented, and by which I mean that it strongly evokes a particular scenario — in this case, the Swiss Alpine setting of Thomas Mann's 1924 novel Der Zauberberg (aka The Magic Mountain). It does this through a mixture of field recordings, samplings of the music referenced in the book including authentic gramophone noises, some minimal piano pieces (presumably from Rabelais?), and significant studio wizardry. And it is, indeed, powerfully evocative of that scenario, to charming and deeply calming effect.
I bought this from Boomkat. They call it Modern Classical / Ambient, Electronic.