It's been at over 25 years since I played in a group where a player actively mapped, back when we'd finish the adventure then spend hours trying to figure out why the left half of the map was two squares off from the right half.
More recently, of course, mapping typically happens on the part of PCs in-game to facilitate "getting back out" or "completing the mapping mission" or "navigating the maze" or whatever, for the sake of skill checks or something. But as a DM, I typically just draw it out as needed for tactical purposes.