It’s an editorial published in the journal of the conference organizer. Calling it an “opinion piece” is incorrect—the journal is still publishing it as part of its proceedings.

Astronomical journals frequently have articles going through the economics of various telescope proposals. The analogy would be someone in management at one of those conferences with an economic stake in one of the telescopes forbidding that team from distributing its work while others continue to do so.

It’s obviously a breach of any reasonable code of conduct. It’s obviously a departure from precedent. And it would make anyone outside that conference really curious about the specific allegations raised in the quashed paper.