I hear so many people complain about feeling the need to be connected all the time, yet the first thing they do when they have a free moment is to check and respond to email.
Pot. Kettle. Black.
No universal standard for responsiveness exists. Instead, each of us needs to articulate our normal timeframe. Call my voicemail and you'll be told that I will respond within 24 hours.
And when our normal timeframe doesn't work for others, it's the beginning of a discussion and negotiation, not a capitulation.
We can't focus on the work if we constantly invite distraction.
Only by saying no every now and then can you say yes to what matters most.