There’s an open source non profit alternative to StackExchange, who knew?! 
Not quite a public dataset, or maybe it is, but certainly in tune with the Safe Network Fundamentals, I present:
Codidact
The Open Source Q&A Platform.
What is Codidact?
Ever had a question? Ever had an answer? Ever had knowledge to share? We believe that coming together to inquire and learn, to share knowledge and to teach each other, makes the world a better place. We also believe that Q&A communities should be free from the politics and shenanigans of private, profit-focused companies.
Community First
We’re building an open-source platform for community-driven Q&A sites. We welcome beginners and experts alike, and aim to empower communities of learners and teachers. We’re funded by seeking donations, not by paywalls, and work with individual communities that want to join us.
The Codidact Foundation
Our non-profit organization, The Codidact Foundation, is made up of people directly from our communities, located in countries all over the world. We’re incorporated in the United Kingdom as a Community Interest Company (CIC), with plans to become a Charitable Incorporated Organisation (CIO) in the future. The organization exists in order to provide a central focal point for processing costs and donations, including opening and maintaining a bank account. You can read more at our initial announcement, or view our Leadership page to learn more
Foundation: https://codidact.org
Q&A sites: https://codidact.com