It's not a filter bubble because by default everyone sees the exact same content, just like our Web search results. We decided early on to filter out things like rape, dismemberment, etc. that we thought were staunchly negative. Also, this app wasn't designed to be a traditional news reader. Instead it features interesting content that's currently being shared a lot regardless of publish date.
That's... horribly pathological. I'd even claim that's bordering on being unethical. Also, it's like the facebookey "like" button, in trying to paint everything in rainbow colors.
There is an issue with media pileup and lack of respect, but sometimes just because reporting is negative doesn't mean it's not real. In fact, you've just mentioned a huge social problem (rape) that happens even in first world cultures and is relevant whether we like it or not, that you decided to filter out.
Which is the usual case with the "irrelevant" "negative" reporting that we can't "do anything about". Actually, usually we can, but it's small, won't stroke your ego, and it's easier to hide your head in the sand and pretend nothing's happening. Because paying attention to food you eat, clothes you wear and electronics you buy is hard and isn't making life more enjoyable for you or anyone you know.
