Fiction about the decline of British aristocracy

I often think about the conclusion to Downton Abbey and Robert’s reckoning with the changing times, especially how it related to his role as aristocrat and the people in their village. Is there a book that captures this moment? I’ve been reading a good bit of Victorian lit, and just thinking about how we got from the era of work being looked down upon by the richest to work being idolized by the richest.

Eta: I’m interested in fiction more than a non fiction account of the decline of the aristocracy.