I think it comes down to fear of failure and rejection. Any social interaction has risks of failing, maintaining relationships builds on getting past various faux pas but so many modern relationships are either transactional or transitory to the point people will ghost each other over minor infractions rather than putting in effort that may not be rewarded.

We almost all have forgotten and/or atrophied skills because of how the Internet and technology have changed the landscape over these past few decades, even on social media like here people have forgotten how to have conversations. Rarely do people make friends or even have a back and forth on social media websites, just chains of replies left for the next soul like a guest book with comments.