No. You explain to them that it is trustless in the sense that thousands of people smarter than both of us have reviewed the code, none of which has reached to a conclusion that Bitcoin does not do what it says it does. If people suddenly started losing coins in their open-source Bitcoin wallet, I'd absolutely not recommend that piece of software regardless if its source code was free to study or not.

I would absolutely not invite them to study an entire repository, line-by-line, to validate such a thing. Just as I wouldn't invite anyone to study the design of a car and its manufacturer's infrastructure, if their cars were caught to suddenly explode. I would simply stuck to not recommending cars that are said to explode.