Which is silly. The reason we have giant social networks is because quantity is a quality in its own right. It increases the likelihood that your friends/family are there as well the various interest one might have.
That is less convenient, which means you will do it less, and reserve your energy for only the closest friends. I don't send personal emails to anyone and I don't receive any either. Email is all transactional. Calling is even more limiting because you have to take into consideration the other person's hours. On the other hand performing these costly signals builds ties so you have a point too. I have been trying to schedule a physical meeting with a friend for a while and something always comes up.
Why is a universal success "imaginary"? Very few people are on Twitter for neighborhood gossip. They want to hear and discuss celebrity news and political developments and tech releases and sports scores. The more people join the network from different countries/industries/walks of life, the higher these signals get.
a bigger, widely accessible success can directly translate into people having small and local successes with it/on it. people have their smaller groups, local stuff, their own success, which may be smaller in scale, within bigger communication platforms.