I really enjoyed this post. At risk of veering into the field of epistemology I wonder if our ability to understand the potential of community is limited by what we feel certain community is.
To go deep as you propose CXOs need to expand their definition of community - and most of all consider what it has the potential to be when it's well integrated into product, engineering, sales etc as you suggest.
Community - if successful - could be multiple things to multiple people in the same company. Tapping into what is meaningful for each set of stakeholders and delivering that unwaveringly: that would be success. At scale, that would require a community team / community function in every department fulfilling a cohesive vision outlined by the most senior community person with buy in from CXOs.
To get to that ideal template we need to do way more experiments than we have done on this front as an industry, and get a clearer sense of what good community metrics are. Excited to try some at Brandwatch and will share what I learn.