> In the update[1] he says it's calming and makes him feel safe. He's happier after doing it.
That makes it more concerning, not less. A quirky hobby stops being quirky when it starts filling a psychological need. Fast forward three months and dude might not want to ever leave his tunnel. Why would he? He feels calm and safe there.
If it's concerning to you to fill a need with a hobby, then you're probably going to be concerned about most people. What would you say are healthy reasons to engage in a hobby, if there are any?
I’d say any of the top three levels of Maslow’s hierarchy. A hobby that helps you achieve feelings of self-actualization, esteem, and belonging is great.
Things get hairy at that second level. If you feel psychologically unsafe in your day-to-day life, there’s something wrong - either with your environment or the way you perceive it - that a tunnel can’t fix.
