Removing item components

[next steeple]

You can remove the component using data remove. If you want to do this for the player inventory. You have to move the item to a minecart, modify it and then move it back

[covert ibex]

i'd like to clarify, any method better than just rebuilding the item in a give command or inline loot table, or using an outside entity

[desert nexus]

technically !<component> is a removal

[covert ibex]

technically yes but it means the item can't stack with unmodified versions of itself

[desert nexus]

you mean the unmodified ones have said component?

[covert ibex]

no, they don't have the !component component

this disables components, it does not remove them

[desert nexus]

except you shouldn't see this on the item

unless the default is not empty

I don't know of any stackable items that have repair_cost by default however

the only method other than ! is to use /give and /clear or if it is outside of a player do data remove

alternatively, you can do a copy_components and exclude the repair_cost

you must also exclude custom_data because it will set a default empty object even if the original had none

e.g.:
{function:"minecraft:copy_components",source:"this",exclude:["minecraft:repair_cost","minecraft:custom_data"]}

this is an inline modifier