Description
Mending stops being something you reroll a librarian for. With this mod, villagers no longer sell treasure enchantments like Mending and Frost Walker. Wandering traders sell them instead, so meeting one is worth the walk again.
Unofficial 1.21.1 port of Truly Treasures by Ineffa, for NeoForge and Fabric. Please report bugs here.

How it works
When a wandering trader shows up, there's a good chance its rare trade is a treasure enchanted book. Mending costs 32 emeralds, and Frost Walker costs 16 per level. Each book can be bought twice. Villagers' book trades skip treasure enchantments, so librarians stick to the regular ones.
Which enchantments count as treasure comes from the minecraft:treasure tag, so enchantments from other mods and datapacks are picked up automatically.
The Villager Trade Rebalance experiment isn't supported yet. With it turned on, wandering traders use different trade lists and won't sell the books.
Config
Settings are in config/trulytreasures.json.
Wandering traders
basePrice: emerald price. Single-level enchantments cost twice this, the rest this times the level, up to 64. Default 16.maxTrades: how often each book can be bought. Default 2.tradeWeight: how many entries treasure books get in the wandering trader's rare-trade pool. Higher is more likely; 0 turns them off. Default 3.treasureEnchantmentFilter:DEFAULT: treasure enchantments villagers would normally sell, without curses.VILLAGER: the same with curses.POSITIVE: every treasure enchantment except curses.ALL: every treasure enchantment.CURSES: only curses.NONE: no treasure books.
enchantmentBlacklist: enchantment ids wandering traders never sell, e.g."minecraft:frost_walker".
Villagers
enchantmentRemovalMode: which enchantments villagers stop selling.TREASURE(default),REGULAR(everything except treasure),CURSES,POSITIVE(everything except curses) orNONE.enchantmentsToKeep: enchantment ids villagers keep selling anyway.
Changes take effect after a restart.
FAQ
Client or server? The server needs it (or your game, in singleplayer). Players joining a server don't need it.
Does it need anything else? Fabric API on Fabric. Nothing on NeoForge.
Can I use it in my modpack? Yes, go ahead, no need to ask.
LGPL-3.0. Developed with AI assistance. Source: https://github.com/traelmyx/truly-treasures-reborn