It’s called Work-Life balance or caring for your mental health.

Experienced a similar attitude to being ‘always on in UK‘. What a miserable life. Work lingers always in the back of one’s mind.
Being ‘responsible for IT’ (whatever that means) I started making  my colleagues aware of their phone settings - in company training sessions :) 
It doesn’t need many to start a trend.

In Germany there are a number of big companies with ’laws’ (fought for by unions) stating you mustn’t answer/send emails outside office hours. (e.g. VW)
I believe those companies haven’t gone under yet ;)