Cancelled my sub when I found that out. Switched to busuu, comparing the two, busuu and Duolingo seem to have different teachings and I noticed that my ability to understand things (comments) in duo is slowly becoming paywalled on the pro(paid) version... Wtf??! Quality of lessons is also seemingly going down.
~~Then I heard they are handing user data to ICE (maybe this is a rumor) but it just pushed me away even quicker.~~
I don't have proof of this so I take this back but am leaving the text so as to give context to the comments below.
Ahhh. I see. So it was some what alarmist. I shall update my comment.