The ‘10’, or the ‘613’? The purpose of Torah was to separate. To separate this nation from ‘the others’. To make them Holy. And, that is the definition of ‘holy’ - that is, separated (for a purpose).
In this respect, the Torah did not, or was not ‘known’ or practiced prior to Sinai.
If you are specifically referencing the ‘10’, the purpose of these was to provide a means of being righteous, it specified the requirements for righteousness. And these were not ‘known’ either before Sinai.
Yes you can/could argue that the moral principles were known, and, they were. Those living in the time of Cain knew murder was wrong, and Cain feared retribution. But, your question specifically asked about Torah. And, Torah was about how to achieve holiness and righteousness. And prior to Sinai, neither of these were known.
Your reference regarding Jacob shows how a nations history becomes part of its heritage And, history makes a nation unique. Torah was more about making this nation separate, rather than just ‘unique’.
Prior to Sinai, righteousness came about via faith, as with their father Abraham. And, prior to Sinai, the nation was ‘being born’, so that it could be separated for the purpose God intended. And, step one was ‘delivering’ them from out of the clutches of the gods of Egypt. Sinai was in some respects, step two.