I can't speak to past expansion since this is my first but the gating of crafting materials is arbitrary and stupid. It's not even consistent across all of the professions. Plus it's not like they're gating anything of value, just my ability to level tailoring up. With older content I am only limited by how much material I can gather or buy. No WoD crafted item is worth using at its base level and the time, money and energy spent to make crafted items useful is prohibitively long. With Herbalism I can gather as many herbs as I want, I can grind out as many pigments as I want, with Inscription I can make as much inscription research as I have materials for and unlock as many glyphs as I want. The only thing I'm throttled by is Warpaints, which doesn't matter because you can't make anything worthwhile with them. With Tailoring I can't gather as much cloth as I want, I can't many bolts of cloth as I have materials for. I am throttled by daily cooldowns and subsist off of a drip feed from garrison buildings.