You're missing the whole thing. For starters, Slack is for work and Peach is for personal. But I think before you dismiss something as "isn't it just x plus y?" you need to take a little bit more time and thinking to try and figure out what the product designers are trying to achieve and how.
Maybe the product designers and product providers should be more explicit about how their product should be used and who their target demographic is, if they want a successful product, rather than making everyone "figure out" what they are trying to achieve and how.
"Figuring it out" might be the point. You do realize that you are referring to some of the very few people who have actually already built an amazingly successful product.
That's rather arbitrary. Lots of people use Slack for both work and personal.
The deeper I look and more I think about Peach, the more it looks like a messaging app that lost it's vision. I feel the same way about Snapchat lately too, but somehow they still have a multi-billion dollar valuation, so I'm obviously not the best one to rate a company/app like Peach.
