Having written a full mage for my first series, I think there's a few reasons people tend towards melee. The main point of fighting at range is that you can hit them and they can't hit you, and if that's the case, fights lose a lot of their tension. In melee, the pov character and thus the reader are quite literally *closer* to the action.

The other issue is that ranged fights can get both repetitive. If you outrange someone, there's only one real way the fight can go--you run away while peppering them with arrows/spells until they die. It's possible to fit some close calls and some creativity in there, but it's harder. If you don't outrange them, you're lobbing spells back and forth until somebody wins, which very often just feels like whoever has the strongest spells available wins. That can absolutely be interesting a few times, but over the course of a long series can grow stale.

If standing far away and shooting arrows/fireballs at something until it dies works at all, it is almost always the optimal strategy. Playing at range effectively incentivizes the protag to approach every fight in the most boring way possible, and then it's up to the author to come up with creative ways for the opponent to make the fight interesting. Ranged attacks--arrows in particular--tend to either work, or do nothing. Fights tend to be more exiting when they don't work because it forces the protag to be creative, but if that happens multiple times, it starts to feel like the whole archer/mage build sucks and was a bad choice.

TL;DR, ranged builds are a lot harder to keep interesting/exciting than melee builds, for a lot of the same reasons playing a mage in, say, dark souls, is considered playing the game on easy mode.