Yes but i would argue that the way we communicate now on social media is a lot more shallow and unfulfilling way to communicate than any of the old ways of talking to people. I can definitely see somebody get lonely when he has hundreds of facebook friends but no actual real friends who give a shit. Sometimes talking to strangers is helpful but it really doesn't change the fact that you might be completely alone after you shut down your monitor.
But wouldn't the fact they have X number of followers/online friends still bring a level of fulfilment/satisfaction they might otherwise have not gotten if social media didn't exist?
And doesn't social media allow people to connect in real life too? Don't those youtube 'celebrities' hold regular meet ups? GAF has its own meet ups too.
I do agree with your general point that social media has made connecting with people feel more shallow, people are less willing to engage in person. I think we've all noticed this and it is worrying as we become more and more glued to our screens, but I suspect there's still a strong level of fulfilment in there that makes the people who are regular users keep coming back.
For example, someone goes online and says they feel like shit, more often not their 'online friends' will rally around much in the same way real friends would. It's less nourishing to the body to not have someone there to hug, but if all you've ever known is sharing your problems online, you may still feel some level of fulfilment/satisfaction. It won't be at all comparable to actually hugging someone and the personal connection you make when you see and talk to someone, but there has to be something there for people to keep using it and dedicating more of their lives to it.