Combining your choice of Email / IM client (Gmail / Hangouts or Outlook / Skype) satisfies 99% of use cases for Slack.
Overall we were less stressed and didn't miss a beat. I'm sure there are industries / companies working in areas that it makes sense - but I don't think it just works for everyone by default in the same way that IM and Email do.
https://en.wikipedia.org/wiki/Skype_security#Eavesdropping_b...
I also remember a ToS change that allowed MS to listen in for quality control purposes.
Didn't the Snowden leaks say that Skype had been used to track terrorists?
By judging their client application, I doubt the serverside looks much better, so a direct backdoor might not even be needed.
From what I can see It's pot luck which machine a message will go on The ios client is terrible There's no channels There's no history half the time (if it pops up in webmail for example), if there is, it's client based not server based
We also use irccloud and slack, they are actually useful - irccloud from a standards base, slack from an ease of use. I don't understand why people have so many problems with them.
How does Email/IM (isn't slack just IM?) solve your problems without causing the same stress?
For both cases we used Slack, I agree with your assessment in that we used Slack JUST for IM. But if you already have Hangouts / Skype, what's the marginal gain from Slack? As OP points out, initially most people start using it for IM (as this is like muscle memory) but then channels grow, get out of hand, and someone needs to input effort to cut back the entropy.
But given the effort that knowledge workers put into email management, calendars, file management, etc. that's already a lot of cognitive load on controlling information entropy on a _daily_ basis. God forbid you work in Sales or something where you're in CRMs all day, and then you need to manage clients / contacts, or a Project Manager ... shit gets heavy quick. And that's all from doing stuff _about_ work, and not really working.
Another use case that's more microscopic to me: when searching for information in archives, it's easier / less stressful to have fewer places to search for files or conversations than more. Knowing that I only need to search my emails / IM/ files (or hell - if you use Google, it's ONE SEARCH BOX in Gmail for all of them!) is a tough hurdle to get over when you're trying to sell me Slack (unless you leverage their email add-in and send most of your emails / files to Slack, but that's a hard sell for any team.)
The marginal gain is lightweight group discussion, and the ability to pull people into a conversation that's already in progress.
It actually lightens the cognitive load of which you speak by organizing information by topic.
https://missiveapp.com/slack-vs-missive (detailed post, with meat)
As foreign as chat is to email, mixing them unleashes unforeseen possibilities, like directly referencing customer emails in dev chat conversations discussing feature implementation.
Making collaboration between email heavy teams (sales, support) and chat heavy teams (dev) easier.
I personally think that using a threaded based UI is more efficient to use than the infinite channel Slack offers even for chat.
e.g. Having your Github notifications grouped into different threads based on branches and pull requests all labeled with a Github label.