Greetings wolfieblitz,
While New Outriders does not have a strict age requirement, we are a casual, family friendly guild that has been around since 1992, and therefore have a mature player base with an average age pretty close to your target. I exceed it easily.
At the very least we expect behavior where adults would be comfortable playing.
We’re part of a multi-MMO guild that re-launched about 3 or 4 months ago, so we have a lot of people still enjoying a broad range of content. We are small to medium sized at the moment (most players on SoR, but it varies) and have regular events scheduled for guild missions, dungeons, and will be heading into raids within the next week or so. People are running tier 1 and 2 fractals pretty much on a nightly basis. If you would like to learn more about us, check out our recruitment thread, or feel free to reach out to me in game. Good luck finding the right home!