I am of the strong belief that humans do not prefer to have a 47th private messaging app on top of iMessage, Hangouts, Facebook Messenger, Twitter DM, WhatsApp, Line, Snapchat, Wire, Telegram, and Signal.
I'm not ruling it out for the future, but we're focusing on building a social experience on mobile right now that does not include chat. There are vastly better chat systems out there than anything we could ship quickly, and it's way more important that we deliver the current steemit experience (plus communities and achievements) on mobile ASAP.
Once that ships, we will re-evaluate the value proposition of implementing a quality messaging platform.
If I'm totally wrong and the feature is that much of an in-demand requirement, then people will use Busy instead of condenser or our forthcoming mobile app. The Steem ecosystem still wins. :)
Our goal is success of the Steem Platform. If steemit.com becomes successful in the process, that's nice, but it's not a requirement.