I believe that you get a "contains adult content" message about our Liberty Canyon Townehomes HOA Google Group because a poster to the group may have used inappropriate language by accident in a previous post years ago.
I believe that the Liberty Canyon Townehomes HOA Google Group was started to send our monthly newsletter electronically. That is why I joined it years ago. I don't believe that it has ever had more than 30 something subscribers. A hard copy of our newsletter now comes in our dues bill and is no longer sent electronically.
All of our five Board members are not subscribed to the Group and with only 30 owners, residents and/or previous owners out of a possible 155 units subscribed I don't see how we can call it a representative of our HOA.
I think of it like meeting some residents while walking my pug dogs, or neighbors chatting over the backyard fence, sharing questions and stories about living in Liberty Canyon Townehomes HOA.
As for your quest to delete an old post of yours -- I did a Google search for "how do I delete a post from a google group" and got this link to how to do it.
Good luck.
I hope this helps.
Regina