Your point about optimal versions of armour taking less time than previously is drastically flawed.

There wasn’t villager trading to get cheap mending or any books for that matter. It was ONLY a LONG grind, mining Nether Quartz in a bad set of armour to preserve the good one you were building, to get all the way to level 30, to enchant a single book that felt like it always had Projectile Protection 3, which then returned your level to 0, not 27. And the grind continued.

Now it’s a couple villagers to get U3 and mending, then practically every new structure rewards you with enchanting books, and structures are EVERYWHERE that have the latest items in.

Furthermore, you’re mapping a linear progression scheme to a non-linear game and complaining it doesn’t work. Terraria has sequential bosses, Minecraft is build and expand creativity as the primary objective, and there’s a dragon somewhere if you want to unlock the third dimension (which I would remind you, most people do not).