that is kind of ridiculous to me... ATF, diff, engine oil, transfer case, PS fluid, etc. all make sense to me, but coolant does not have real quantities of wear particles, etc in it, and it is pretty highly additized these days with superior longevity.
3 years 36k miles is the earliest Id do coolant unless you were switching chemistries. Otherwise, leave the system closed and alone...
Keep the radiator fins clean - that is a better project!
JMH