[1] https://blog.wolfram.com/2019/04/02/why-wolfram-tech-isnt-op...
[1] https://blog.wolfram.com/2019/04/02/why-wolfram-tech-isnt-op...
And many, many amazing open source teams have demonstrated that even including community driven design in some cases does not hamper the quality of the product. Look at Apple and Swift, or Rust, as examples.
I read their arguments as “we do not know how to engage with a community effort because it’s not in our company DNA” under the facade of supposedly legitimate reasons.
Rust I'm not very familiar with: how much of their funding is dependent on Mozilla, at least for the core developer(s)?
Also, a language + a standard library has a (much!) smaller surface comparing to Wolfram's vision.
If Wolfram’s reason to not publish the source code is that they believe they would no longer have a business model, they should list that as the One Reason, not 12 gaslighting reasons.