Selling tools to prospectors
It's tempting to say this is another Dotcom Bubble, but I think the dynamics are a little different. There's not as much cheerleading going on from the financial media as there was back in 1999, and companies aren't shipping 50 pound bags of dog food free to customers. But, it seems like these "startup/DevOps work tools" vendors would be taking the place of the e-commerce companies if we were to project the present back onto 1999/2000.
I guess we'll see what happens after the founders become instant billionaires. But Slack has competition, including Microsoft who is basically making Teams "free with purchase" for O365 subscribers. They're both super-bloated JavaScript front ends to instant messaging with similar features, so I wonder what the distinction is besides "not a Microsoft product" -- other than "Unicorn Startup X and Y use Slack."