Because besides incredibly few exceptions no one uses another Smartphone App for me, no one wants to have an explanation how IRC works, and E-Mails seem to be good for everything but writing to me.
No one will change their behaviour in any regard just for me. Maybe because I am not one trying to force something down other people's throats, that's not my style. Maybe you were one of those hardcore social media users people couldn't live without, but for the occasional twice a month conversation online and the 1 like a week, I won't be missed nearly enough.
And this is also the sentiment I have received multiple times from others who have abandoned social media at some point. So I strongly suspect your case is an exception and not the norm, and maybe you are portraying it as a little bit easier and positive than it was or is.