> Leave your phone on silent permanently, setup your emergency contacts like partner and kids to ring on silent, and turn off all notifications except email and SMS/WhatsApp. That’s the key to a simple life. You won’t miss anything important and that realization is the most freeing

This is pretty similar to my setup. Always on do not disturb. Typically my family and close friends communicate through a chat app, that doesn't make sound but if it's time sensitive an sms or call will make sound for starred contacts.

Back on the day when phones had notification LEDs I'd setup apps to have specific colours. These days with always on OLED displays I use an app aodNotify to setup a a little spinning circle on the screen. Purple is family/friend chat app, blue is a call, green sms etc.

Everything else I periodically poll for information. ie I go out of my way to check emails etc