I tested this a few times to make sure it wasn't a fluke, but it seems that the durability changing on any other item you have awards you the achievement regardless

You did not give us enough information to be able to properly assist you. Namely:

• What version of Things?
• Any other mods? If so, what is your mod list?
• Which modpack, if any?

Apologies about that, anyway heres a run down of my current mods:
Currently running 1.19.2 of Minecraft

Current mods, and I am not playing with any premade modpack.

Things v0.2.200+1.19

Trinkets v3.4.1

Patchouli v1.19.2-77-FABRIC

owo-lib-0.9.3+1.19

charm-fabric-1.19.2-4.4.4

Hopefully this helps!

Thanks for reporting this, it has since been fixed in release 0.3.0
Cheers