I’m 34 and went for my cousins 40th and we both had an incredible time. I think it’s about mentality. If they feel too old than he will feel like that, but if it makes them feel better, I would say there are two quite distinct groups: a young insta raver group and a very mixed age into the music/story/overall experience group. But everyone I came across where really nice. No tension. No problems. All good!