Earlier quoted context omitted.
This is absolutely true and shocking difficult. You can disable every notification on your phone, mute all non urgent email, change the way you read news, block social media for a day or delete it permanently... all the small things help. But the worst interrupters are the hardest to tame. If anyone has a Slack containment strategy, I’m all ears.
I just turned slack off and check it every couple of hours. No one has shouted at me yet.
Helping others is one thing. Doing it at the expense of your own productivity is another.
Silent phone is easy for me. You can always make the bosses VIP. Also I have never installed email or Slack on my phone. My current workplace is relatively low volume (50 or so staff). I can't imagine how it must be with a lot more.