I've someone has gone so far like Apple already did, I doubt that a open letter will change their thinking. Maybe they step a little back and bring the next similar thing which looks less invasive some time later?

Thinks like this must to be stopped! Customers shall not buy anything from companies which are hostile. And laws against these usage need passed. As far as it looks, the laws in Europe are in place and prevent this currently. But just currently, we've seen how companies like Apple push the boundaries. We as humans behave totally irrational, we complain about inhumane working conditions at Amazon and then we order the next item. We complain about a golden prison from Apple and buy the next iPhone. We should change?