No chance I can do math in my head nearly as well at 30 as I could at even 25, but I can't count the other areas I have improved in that seem to mean so much more as an adult and as a professional.
For example, I couldn't learn other languages so well as a teenager (I wasn't such a great grammarist with English either). As an adult I've picked up French rather quickly and grown fascinated by linguistics; hard to understate the positive effects this has had on my career and even social life. Take all of that and the real-world job experience, add it to the calc and CS coursework from university and I'm 100x the developer I was 5 years ago.
For example, I couldn't learn other languages so well as a teenager (I wasn't such a great grammarist with English either). As an adult I've picked up French rather quickly and grown fascinated by linguistics; hard to understate the positive effects this has had on my career and even social life. Take all of that and the real-world job experience, add it to the calc and CS coursework from university and I'm 100x the developer I was 5 years ago.