There are quite a few people who are under 30 also. You must be 18 to contribute though, so that lets out the teen ages. The people here have a wide variety of interests and read a lot of different type of information. They write stories for children as well. Many do not write for the HubPages community. They write for Google searches. Since Google searches for such a wide variety of topics, there is really no reason to tailor your writing to the community.
Write what you enjoy writing and enjoy your time here. People will read it and hopefully you will thrive here.