I think what Warnie Lewis was responding to, in F. F. Moore's novel, was the way families lived in that time. He seems to have felt a real sense of recognition. He particularly mentions tension between fathers and sons, and fathers chronically needling sons -- "catching them on the raw." What Warnie had seen more as an exasperating quality of his father's personality, he came to think was (as we'd say now) part of the culture.
Well, here, I'll quote Lewis, writing in his diary 20 August 1967 of Moore's 1914 novel --
---After tea I began to re-read The Ulsterman and found it as good as ever -- a burning, bitter, but lifelike picture of the Ulster of 1914. The most interesting thing is to find that the dominance, the ceaseless cross-examination, the unawareness that J [C. S. Lewis] and I were individuals which we thought was Lewisianism was in fact Ulsterism. True, we were never treated so badly as the Alexander family but in what follows there is enough our own adolescent grievances to give more than a hint of Leeborough [life at Little Lea] conditions. ... [And Warren quotes from a part of the novel I haven't reached yet, including the following -- this is Moore now:]
--You know the relative position of father and son in Ulster....The son is in a worse position than the errand boy. You know the way we have to give an account of ourselves wherever we may go. If I go as far as Belfast for a day, I'm cross-examined as to how I spent every hour. ......The true humour of the Ulsterman ...consists in the probing of an unhealed wound -- the touching of a raw place with the broad tip of a finger fresh from the pot of red pepper. [etc.]
Back to Warren:
---True, and to me only too familiar. ...he continued to jab at the sore place for the rest of our joint lives. But worst of all was the fact that from the end of the war until the last time I visited him I doubt if he ever let 48 consecutive hours pass without some offensive sneer at my [military] profession---- [etc.]
And Warren was saying that this sort of thing wasn't simply a vexing peculiarity of his father's personality, but was typical of the Ulster milieu.
Moore mentions the money-worship thing, and I remember that in a different book, about Lewis's Belfast heritage, it says that there was a commemorative plaque listing those who died in the Titanic disaster -- "in order of social rank, with the wealthiest given prominence." Warren said, "In the upper-middle class society of our Belfast childhood, politics and money were the chief, almost the only, subjects of grown-up conversation: and since no visitors came to our house who did not hold precisely the same political views as my father, what we heard was not discussion and the lively clash of minds [such as, e.g., prevailed at the Oxford Socratic Club with which Lewis was so involved in later life], but rather an endless and one-sided torrent of grumble and vituperation. Any ordinary parent would have sent us boys off to amuse ourselves, but not my father: we had to sit in silence and endure it," etc. Here I'm quoting from Ronald Bresland's The Backward Glance: C. S. Lewis and Ireland.