You are mixing up the need to separate accounts &#x2F; identities (which even single client can easily do even for the same service), and artificial separation of services caused by the lack of interoperability. Those are completely unrelated issues (first is something that user should have a choice to do, second is something forced on the user).<p>I explained it here as well: <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10856612" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10856612</a>