Ah ah, the first link is yet another interesting "it makes sense" post from Raymond Chen.
The second link is saddening and I know iMessage is a problem in some areas of the world. Here, people expect that most people don't have an iPhone… and the problematic messengers are of course Facebook and WhatsApp. At least, here, it seems that most people understand that you don't want to use them. But you are still locked out of group discussions. You rely on people who like you to keep you posted because they want you to be at whatever event is being discussed there, and you are that one person who is not in the group chat.