I'm going a little offtopic here, but I disagree with the OPs use of the term "PhD-level knowledge", although I have a huge amount of respect for antirez (beside that we are born in the same island).
This phrasing can be misleading and points to a broader misunderstanding about the nature of doctoral studies, which it has been influenced by the marketing and hype discourse surrounding AI labs.
The assertion that there is a defined "PhD-level knowledge" is pretty useless. The primary purpose of a PhD is not simply to acquire a vast amount of pre-existing knowledge, but rather to learn how to conduct research.
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