DM-first is an extremely frustrating culture. That kind of operation tells me that that folks are too risk averse and political to discuss things openly. Typically this is led by panicky managers that are worried about involving too many people or having to explain things to folks they don’t want to deal with, and it escalates from there and gums up ALL the things. It makes Slack basically useless.

The same people DMing however will also extol the virtues of posting in public and lament why there is not more conversation happening in the open.