I have had a number of mesh-back seats through the years/bikes, and believe they do a pretty good job ref reducing "sweaty back syndrome." I still get very sweaty, but there is no pooling effect.

The technical clothing, whether designed for bikes or not, does a good job of wicking moisture and it dries much faster than cotton. They do much better than cotton at reducing the chill in colder weather once you do get a bit sweaty.