The official app isn't a bad thing because it's buggy and has ads, that sucks but I've used much worse apps that offer less. The amount of ads and how easy they are to click accidentally is ridiculous though
It's bad because it's built to do what Facebook did - it always gives you something to see and a reason to keep going. Have a nice, curated mix of science and shit posts? Let's throw some crap from the front page in there along with the ads! No one responded to your comments? We'll make suggestions look like someone is interacting with you! Haven't used the app in a few hours? Here's some posts delivered in a notification to get you back in there
I left Facebook for Reddit because I realized I didn't really enjoy it and often ended up feeling worse after using, and when the experiments they were doing came out I payed close attention. It was a real slap in the face when I saw Reddit doing similar stuff, and I checked out alternatives like tildes but nothing else was scratching the itch so I put it on the back burner.
For those of us who aren't going back, this wakeup call was a blessing. It's a strong reminder that corporations not only don't care about us, they can't - they might act friendly sometimes, but they wouldn't hesitate to poison the water supply if they thought it would bring greater profits