Same here!
I’m in my mid-30’s now. In high school I learned HTML because I really wanted to customize the styling of my Guild (I think that’s what it was called).
And then built a neopets fan site and forum which taught me basic business (trading links with other fan sites, hiring/managing forum moderators, and eventually sold the fan site during junior year).
The will to customize my MySpace profile was also a driver for learning HTML.
I sometimes think about this in the context of today’s highly controlled platforms that simply don’t make space for users to customize or do anything outside the platform directly.