There's a few things that could be done. Whether they would work to the result you, or many other users, will consider positive remains to be seen. I find fatalistic approach to system design rarely beneficial.

Here's one suggestion:

Clear fuckin' everything. Remove all content from this forum, and all users. Have all users that are still interested in participating in a new format (TBD) re-register, using previous or new usernames. No archives, no links to previous threads, no saved settings. Reboot.

Then have the users wait for a month without being able to engage with Hubski at all. (Ideally that would also mean not engaging with the same people from the previous Hubski via external contacts, but that's an honor-system contract not everyone would sign, so you can't rely on it.) No messages to mk, no posts, no comments, no chat.

Then you let users come back. Maybe you tweak a few things about the forum engine, maybe you don't. Fresh start. Clean slate.

Here's another suggestion:

Only ever open Hubski to interactions once a week. Host Pubski on that day, let users post links and make comments. Once your timezone-based 24 hours are up, hope you said everything you wanted to say, 'cause it's Monday o'clock, the bar is closed, and you're on the curb.

Not one thing will work if you, a member of the community, is willing to give it a shot.

Complacency is the mind-killer for places like these. Change is good.