I'll throw in some generalities to explain the age situation:
1. The course is very full on with limited leeway for catching up. When was the last time you studied full time and intensely for an extended period?
2. As you get older it becomes harder to learn entirely new things and change the way you think. On the course you aren't just learning facts and rules but also a way of thinking.
3. Having other responsibilities such as family can be a distraction.
Hempy isn't meaning 40 is some magical cut off but the older you are the lower your chances of passing are. Multiply that by the factor of relatively few over 40s starting training and you end up with numerical scarcity. Again all very anecdotal.
Those are the "stats" such as they are. In the end it all comes down to you as an individual. All it says that you at 36 will likely find it harder than you at 26.