The problem with that is assuming they will have internet connectivity always on when you want to contact them. Which I never found true even for the few people I regularly communicate over Signal. Most people turn off data and only turn it on somewhat regularly over the day to check stuff. Older people (like family) have no idea or barely know what internet is or even the button for that does and just expect communication to work like always: sms and phoning. But if people cam do the above approach good for them. I can barely convince anyone, even tech people from work or friends to install even more chat clients/services. Most are just fed up and feel tired of the whole thing.
To save money, battery and potentially protect weird apps trying to abuse the use of internet on background. Have heard and seen so many justifications for it. Barely know people that have internet 100% of time on. Somewhere in Europe ;)
