Even a technical lead of an instance may not have read every single line of code because codebases these days are pretty large. Typically you might look at the code you’re working on, but not necessarily the entire codebase.
Hopefully Lemmy doesn’t have anything malicious in it, but it’s possible to sneak malware into open source projects. This sort of thing happened to XZ Utils last year.
Yeah I’ve heard of that, maybe I should look at it more. Hopefully the Lemmy codebase is fine though. I’m just saying it’s possible, even if perhaps unlikely, that something could be lurking in the code which nobody has discovered yet. The XZ Utils backdoor was well-hidden and happened to be discovered, but maybe malicious code isn’t always discovered.