It’s my understanding that it’s open source, but I unfortunately don’t have the competencies to review code and see where every piece of data is going and what is actually logged.

I am a beginner software engineer and I kinda have no clue about many parts of the source code too, but one thing I could notice is that there are lot's of people that are actively contributing to the source code. I hope if lemmy tries something funny, the open source contributers would be the first people to call it out.