Going by Kreb's analysis of the attack [1] it would appear that the breach was a run-of-the-mill SQL Injection attack. Proper security 1-0-1 stuff.
[1] http://krebsonsecurity.com/2015/10/talktalk-hackers-demanded...
[1] http://krebsonsecurity.com/2015/10/talktalk-hackers-demanded...
As a colleague developer of mine says: I don't want any of my personal information on the internet because I know how developers think.
Sigh.
At that age you have intelligence, lack of considering consequences and importantly lots of time. That's a dangerous combination.
I would think that the 50+ crowd would be far more hampered by their risk assessment of the negative outcomes of these behaviors than by their skillsets alone.
A teen is in it for the lulz, or the glory, or whatever, but a greybeard could lose his retirement, leave his spouse high and dry, lose his ability to see and support his family...