Agreed. If anyone feels some kind of way about you leaving a Slack channel, parent's company is using it wrong. I'd kinda guess parent's corporate culture also

Agreed. If anyone feels some kind of way about you leaving a Slack channel, parent's company is using it wrong. I'd kinda guess parent's corporate culture also tends to accrete huge email CC lists? As that's the same human problem: add, but never remove. And also, Slack search by default is global: you don't have to be in a channel to get a search hit.