It's incredible that Discord leap frogged Slack as the consumer/SMB alternative for work related discussions over pricing. Teams basically ate them from the high end and Discord from the low end. This is a one example of pricing being the killer feature in more ways than one.

It's more than that, I think. Slack holds hostage your conversations, documents, and institutional memories. At the free tier. Somewhat even at the paid tier. That positions them as untrustworthy and extortionate rather than as a friendly partner.

...and attempted to establish a policy where all non-NDAed conversations take place on Matrix so that the community could stay involved. Which approximately no one paid even a tiny bit of attention to.

I'd say that's a lot more complicated... Slack happened before Matrix. Barn door, horse, etc.

I get that culture change is hard, and incumbent solutions build a lot of momentum; but the rationale behind the policy is sound, and I think the project is significantly worse off for not taking it seriously.

Before I joined Moz, I was impressed at the incredible ease of access to contributors and developers via IRC. After departing, I'm impressed in the other direction at how hard it is to contact anyone via Matrix outside of a few select teams (props to autofill and IPC for caring).

There's so much to unpack on this front. First, culture is people, and we're generations down the road from the people who created that original culture. Second, openness is a huge pain and always was... but the contributions we got from the community made it worth it.

Third, over time, and for no single reason, the ROI on community investment declined to the point where it wasn't always a positive. And for teams that didn't get help, working in public was mostly a negative experience.

All in all, there's no single factor why things changed, but IRC/Matrix is really not the root cause. Blaming Slack is missing the point.