Backstory: Slack can easily be the biggest daily distraction. You can go down the rabbit hole of fomo with reading every message in global channels or get stuck responding to everyone's direct messages. Sometimes it's a lack of process but it can be the tool choice as well.
The Idea: A slack alternative that offers less distractions and more time for deep work.
Deep Dive: This is quite a lofty project, you would have to build a massive feature set to compete with slack to even be considered an option for larger teams, your target market. Smaller teams don't feel the pain of slack distractions because there are so few people in the project.
You would have to take a definitive stance against direct messaging/alerting and perform a lot of user tests and experiments before building too far in one direction.
Validation: Derrick Reimer, co-founder of drip (my favorite ESP!) started down this path with level: https://level.app/. He recently decided to end his year long task; deciding that the vast scope of the resources and effort didn't fit his person vision/ethos. I still think there is opportunity here, it would take deep pockets or early dilution to start. Read all about his decision to shut down level here: https://www.derrickreimer.com/essays/2019/05/17/im-walking-away-from-the-product-i-spent-a-year-building.html.
Monetization: Similar model to slack, you would charge per seat.