It seems to me that there are more regular contributors in the 60+ group than in the 50-60.
When you suggested a 50+ forum, I thought a 60+ would be of greater value. I was going to mention at that time, but the 50+ forum was created very quickly after your suggestion, before I could comment.
I still think it's a good idea. I don't think the threads would get fewer views or less participation. I have greater respect for 60+ riders than 50 somethings. A forum for 60+ would be a recognition of lifelong cyclists and a place for the rest of of to learn from their experience.
But if no one likes my idea, that's OK.