Internet naturist forums attract mainly people who have no network in the real life, or who love to discuss with strangers, or who are activists and see the Internet as a good tool.
People who have naturist friends in the real world often dont' need to look for more friends via the Internet, and they can enjoy face to face discussions. And some activists prefer to focus on local communities (a beach, a campus, a network of associations, etc.) to promote naturist than on (or mainly in) the Internet.
So, I think your decision is very normal and logical.
For account deletion, I don't know how it works. I expect people who knows will answer.