https://slatestarcodex.com/2017/07/31/book-review-raise-a-ge... is about essentially a very similar style of intensive individualized tutoring. (This SSC review links to a new English translation iof this work.)

I'm not sure that intensive tutoring ever "went out of style" though, so much as gradually becoming infeasible because of (1) the amount of high-skill effort involved, which became more and more costly due to the expanding alternate employments of similarly skilled work; and (2) general progress meaning that even with intensive tutoring you could not reach the research frontier any more effectively than others, so making "genius"-level contributions would still be hard.

It's an interesting argument regardless, and intensive "tiger mom/dad" parenting, while generally less effective, still derives much of its general orientation from these 'aristocratic' norms.