I don’t because I don’t see Disqus as competing with Discourse.
Discourse is clearly focused on one community at a time. Disqus is clearly focussed on comments for published documents such as blogs in more than one community. The idea of community is compromised in ways that the Discourse team will never allow.
You are right that there is clearly an opportunity to leverage Discourse - and thanks for expressing yourself so clearly and politely. And it would be easy to take that path But the opportunity cost is way too high when core Discourse has so much more yet to be realised on the road map.