FWIW it's not something I asked anyone to do. The practice started organically and continues to exist because everyone created their own channel and kept going with it.
One thing I suggested was that they should be muted by default so that they aren't a distraction and don't set the expectation that they should be read.
I thought it would be interesting to write about because it was an emergent practice that seems to be sticky and useful within our team.
As a CEO 'manager' myself, I try to let people just be. Getting too granular about person vs. topic and redirecting people to the right room sucks the fun out of everything. Let people mess up and post in the wrong place, who cares?
OP's post was about a great experience 'tremendous value' they had and now you're pooping on it with 'manager' opinions. Read what you wrote from the employee perspective, you're sounding like the self-appointed fun police.