If everyone cared about each other and were good, wouldn't there be less loneliness and more friendship?

The Childlike looks to and expresses soul; such naturally loves, much as Descartes expressed God's thoughts, so too the soul expresses God's lovingkindness.  What may seem complex but really isn't is the monism of God and man in God's Image and likeness.  A sin-derived veiling makes the simplest of Love perplexing.

the inspired Scriptures also foretold that in our day, a misdirected kind of love characterized by selfishness would be shown by people who are alienated from God. The apostle Paul wrote: “In the last days . . . , men will be lovers of themselves, lovers of money, . . . lovers of pleasures rather than lovers of God.” (2 Tim. 3:1-4) This self-centered kind of love is inconsistent with Christian love; it stands in contrast with it. Pursuing selfish goals does not bring people the happiness that they expect. Indeed, such love fosters a selfish world that is “hard to deal with.”

It is complicated.  Loneliness comes from not feeling heard or understood.  You can be friendly and feel lonely.  

Friendship is tough because it’s making yourself vulnerable.  If you here ever been bullied at 3 or at 30, trust is tough.  That makes life a little lonely.I am friendly with everyone—I like people.  But I can be a aloof with letting people get too close.  I’ve been hurt so I am slower opening myself to that vulnerability.  So sometimes I feel alone. My safety is more important to me.   Sometimes I put the breaks on when I catch people being manipulative.  This is learned and self preservation.  I’m also not as tight with the “life of the party” because I dated one and it was a horrible couple of months. He was attention seeking and self absorbed.  Such people can exhaust and hurt their mates and partners.  I’m kind of done with big egos.  They aren’t comfortable in their own skin so they make up a character.  They aren’t always capable of intimacy. Then there is gender—committed people have to be careful, and draw lines in the sand. So I have male friends but they aren’t people I focus on. We don’t text much  or speak deeply to that often because it would worry our partners. Social status is not an issue for me but I can feel uncomfortable with some rich people—especially the condescending ones.  I also kind of give up with people who talk all the time and don’t listen.  It’s just parallel play.  I want friends with integrity and kindness—people who can listen as much as they are heard.It helps if they are interesting too, but not a requirement. I’m all for having fun, but not at the expense of others. I want friends who care.   Sometimes these standards make me lonely.  

 Theoretically, yes, but without it actually happening there's no way to prove it and, like it or not, the world isn't going to change for you. It's a "pipe dream". All you can do is control yourself.