Yes, age will be starting to take a toll in terms of reflexes etc.
However, DC is the kind of fighter for whom age-related decline is least significant, as his style is very much based on technique, rather than physical attributes.
The best analogues to this can probably be fouund in boxing rather than MMA: think Archie Moore, George Foreman, Bernard Hopkins.
Really solid technique sees this sort of fighter through, after the quickness, flexibility and raw strength of youth start to go. (C.f. Roy Jones Jr., whose career fell off a cliff with age.)
DC's also fortunate in that he's a fighter with power
, which is thought to hang around for a long time after other abilities deteriorate: