When I was in my early twenties, I thought paternity tests were something reasonable that maybe everyone should do, just to avoid possible problems in some cases.
I have to tell you, now I have kids and did no paternity tests. My wife and I love each other immensely, we wanted kids, we tried until we got them. It would be insulting to suggest a paternity test on that situation.
If it was general public I’d say D&D or Linux, for sure. On Lemmy, I guess I would say Pathfinder 2e and Kubernetes.