The reason that we highly value their words is because they are closer to the authentic mesora. Not because they are naturally smarter or better writers.
This is not true. We consider previous generations smarter. See Ramba”m in his hakdama to Pirush Hamishnayos. It is generally assumed to apply to all subsequent generations, and the general approach of each generation’s talmidei chachomim to those of previous generations bears this out.