Disc golf. I started playing during COVID. It's the first new hobby I've picked up in over a decade.

If you have a course nearby, it's a really accessible sport because all you need is a couple of plastic discs. It's a great way to get outside and walk a couple of miles. Plus it has a lot of nerdy elements (disc flight numbers, release angles, form, plastic types, etc.). And for me, it's fun whether I'm playing by myself, with friends, or with my kids.