Notifications have this huge downside that they disturb you from your work and from your leisure time, fragmenting attention to the point of being useless to yourself.
This has long been decried by people like Cal Newport and others. Knowledge workers need their attention span intact, and yet all the modern tools make interruptions more likely.
I've been in a Messenger group of only 5 people, who were trying to synchronize going to the movies. My phone kept bleeping for 5 damn hours, until they figured what to do. Absolutely disgusting.
Also, if your friends are making an effort to keep in contact with you, why are you faulting them for choosing X medium instead of Y?