Agreed. Just last year The Economist had a short article on the popularity of self-help books in China[0]. It's estimated almost a third of all books sold in the country are self-help books.

If anything I would expect self-help to be more popular in less well-off countries, where there is perhaps more incentive to be hyper-competitive to try get ahead.

[0] https://www.economist.com/china/2020/11/12/why-self-help-boo...