It would be cool to be able to turn this off. It would be even cooler if you could get rid of Too Expensive when adding enchants from books but not when repairing tools.

The first part can be quite easily implemented with this mixin

@gnembon I can send you a pull request. Do you have any preference/policy what rules go into carpet, carpet-extra, or third party mods?

Until then, you can use the anvilTooExpensive rule in Anvil Crush, @3mstav.