I have to disagree on that being an obvious assumption for the meaning of "from scratch", especially given that the book description says that readers only need to know Python. It feels like if I read "Crafting Interpreters" only to find that step one is to download Lex and Yacc because everyone working in the space already knows how parsers work.

> I suspect the don't really understand what's happening under the hood or how contemporary machine learning works.

Everyone has to start somewhere. I thought I would be interested in a book like this precisely because I don't already fully understand what's happening under the hood, but it sounds like it might not actually be a good starting point for my idea of "from scratch."