It's sort of a bad thing to do, but you will start getting fewer Slack messages. People have an implicit understanding of who's likely to respond in a timely manner, and somewhat ironically, it's the most responsive people who have to improve their responsiveness even more because by being responsive they'll get even more messages and interruptions.
On a meta note, it continues to surprise me that more people and companies aren't talking about the highly distracting effects of the software. It works great at small scale, but if you get large enough everyone's pinging everyone all the time. I recently read Deep Work by Cal Newport (excellent book by the way [1]) and couldn't help but being mildly entertained when they get into the time draining effects of email (it seems to have been written a little before Slack caught on). The distraction engine created by Slack is the SR-71's Pratt & Whitney J58 [2] compared to email's 5 HP motor out of an everyday golf cart.
[1] https://www.amazon.com/Deep-Work-Focused-Success-Distracted/...