A lot of regret actually comes from enjoying something and then later realising that it was stupid and a waste of time. Time that you would have liked to spend on a more useful endeavour.

A lot of your personal regret might come from that. I think it's important to note that there are many people who can look back fondly at times they were simply enjoying themselves, even if that time was not strictly 'useful'.

The joyful days of configuring vim. You are trolling me at this point.