There is definitely a cost. I've spent an unhealthy amount of time alone in my life. I even used to be proud of how long I would go without talking. Much of that was caused by untreated social anxiety. It was easier to sequester myself in my dorm or apartment, and study or work remotely.

The result is that yes I found ways to cope without human connection, including imagining that I wasn't alone, but they make it far more difficult now when I do need to socialize, I feel all the more isolated and awkward.

Also not all human connection has the same value even to an extreme introvert. Like texting and such is OK, but a lot of times ppl are afk, so I might be in a very social mood but not able to satisfy it. Books, movies, games don't really "scratch the itch" for me personally.