I'd ask the doctor. I'm taking a guess that he meant your colon is quite redundant. Women tend to have a slightly longer colon than men. I know the only tough time we have w/my scopes are in the transverse colon. My gastro swears mine dips down to my pubic area! The colon is very flexible to begin with. Its not always that nice upside down U shape we see in the drawings. I fail to see where age would have anything to do w/that.
The only other thing I can think of is that he might feel it is too thin and might more easily perforate. "They" say our skin thins as we age, maybe he thinks your colon wall has as well. You almost have to ask the source what he meant.
Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.