Ah gotcha. I don’t know of a foss version but you can use Buzzkill or STFO to make a notification rule that turns up sound for a matching text message or something like that. I.e. send a text “ring my phone” and make a rule for it to do a sound

https://www.google.com/android/find/

You can use the play sound button to make it ring

I think a second factor is a lowered expectation of immersion that comes with playing elsewhere. The author specifically says they can play in the pub waiting for friends or on the train or whatever. You’re not as invested in those situations, so a game is more of a distraction than an experience.