It might seem counter intuitive that hiding your interface stops your users leaving. But it does it because it changes your basis of assumptions about what a device is and your relationship with it. It's not something you "use", but something you "know". They want you to feel inherently linked to it at an intuitive level such that leaving their ecosystem is like losing a part of yourself. Once you've been through the experience of discovering "wow, you have to swipe up from a corner in a totally unpredictable way to do an essential task on a phone", and you build into your world of assumptions that this is how phones are, the thought of moving to a new type of phone and learning all that again is terrifying. It's no surprise at all that all the major software vendors are doing this.