> I know what they meant.
If you did, "Trade secrets are a type of IP." seems to be an unrelated assertion to the thread.
> You would be sued under trade secret law if you intentionally leaked them.
To embed trade secrets into an open source fork, would suggest either the intent to withhold the modified source, ignorance, or flat out incompetence. Anyone, be it a lone hacker or a large organization, can simply fork the source on the platform it's hosted on (e.g., GitHub, GitLab) at a click of a button.
It is a requirement of AGPL that all deployed updates to a product or online service need published source[0]. Once again, very simple to have this running off CI/CD. If there are trade secrets in that source... oh well, they have to be published too. So the simple solution is to not have them in there in the first place (i.e., abstract it away).
[0] https://news.ycombinator.com/item?id=40032179