[1.15.2] No way to prevent enchantments from appearing in villager trades or on vanilla enchanted books.

Why do I need to do this? Because every mod should have a config. I want users to be able to disable any of my custom enchantments they want. This should mean they don't come in the enchantment table (done) as well as not appearing in villager trades and not appearing on vanilla enchanted books that spawn in chests.

Lex says this is possible using the following: "By not listing them in the loot table that generates the books, or the list of villager trades.". Pretty sure that's not how these things work.

I had an idea to use a loot modifier to remove enchantments that have been disabled in the config, but Lex insists "You shouldn't need loot modifiers to remove them from the tables. You should just NOT add them to the tables."

So could anyone who knows what they are talking about explain how you can do this in 1.15?