If you trust those """services""" to be secure and trust that they care about your privacy, then you will be betrayed sooner or later, in ways you can't think of -- just like in the article.
Fun fact, years ago I accidentally found out that my girlfriend at the time cheated on me on Snapchat, without me actually exploiting anything. She told me to join it with her, telling me that is going to be fun. Snapchat kept track of useds' activity and gamified it to incentivize you by scoring your activity then. Each person has a public activity score when you tap on their profile. One day, I noticed that her Snapchat had more than twice the score that I had. So I clicked on her profile and there it is some strange dude having a score higher than me, it turned out that was her """"ex"""" (I actually never asked her even for his name before, I found out only after that). I never consciously looked for anything, I trusted her 100%, the score was just there on my screen.
Thanks Snapchat for their stupid gamification efforts, otherwise I would have wasted more time on her. But since that accident, I never trust proprietary shit that has money to make, ads to sell, governments to please, and incentives to grow, even it says its selling point is to protect your privacy, like Snapchat. It's not about the "end to end encryption" or "finer privacy control" or "only allow when app is in foreground" or "restricted sharing" or "MIT open sauce license" or "export your data" or "only listening to hotwords" or "open APIs," it's about the intent. If the intent was to expand and make money, then all those techs won't be the magic pill that suddenly cures the ill intent. Anyway, privacy my ass, man.