Having lunch with colleagues has nothing to do with 'backchannel communication'. Sometimes it's nice to hear about where we like to go camping, or what cities are nice to visit in their home countries, or ... nothing to do with work or shipping products.
No matter how 'correctly' you think you're doing things, you still haven't convinced me after over a decade of shipping products that online whiteboards are useful, or refuted any of my other points.