This is an app that will not work in the west. And frankly it shouldn't. It's an insult to the intellect of an employee.
But there's other alternatives to slack, such as Zulip
People will sell their privacy for far less than we imagine.
And it's not just the modern web. Anyone remember the Outlook plugs that gave you smiley faces, when in reality it was ubiquitous tracking and advertising malware? Your privacy for an emoji.