Incent would be an example of a project that has largely moved away from using Bitcointalk on a regular basis.   The only reason that I spotted your message was because Incent has a BitcoinTalk thread in their Slack that posts the text of new replies.  Incent's latest tweet is in fact an invitation to join their Slack.   

https://twitter.com/IncentLoyalty/status/1043643637081485312