When I was a teenager, I felt like 40+ was so old that your life was pretty much over and not worth living, but I've done so much self-actualization since my mid-30s that I'm still unlocking many of the things I hadn't previously thought I could do, like find a job I actually love, create stuff I'm proud of and have gotten positive feedback on, getting recognized for my skills and interests, etc. It's unfortunate that it can take a while to get around to doing some worthwhile stuff, but it's better now than later, regardless of what age you are. Thinking there wasn't much more after 40 was just a limitation of perspective on my part.