The amount of effort that goes into extracting and smelting ore makes it prohibitively expensive to make metal arrows. This is doubly true since you can collect ironhead and poison arrows from Sunken Crypts as you collect iron scrap. Why make what you can scavenge?

There are only a few arrows I will ever make. Wood arrows are my go-to hunting arrows, good for game and unsuspecting targets. I will make a stack of fire arrows to kill The Elder (and save for growths in the plains). Poison and Obsidian arrows work wonders against Moder. Once I'm in the plains, poison arrows are excellent for sniping fulings. Needle arrows become my general use arrow for anything bigger than deathsquitos.