Clearing key bindings impossible?

[Kerouha]

Is there actually no way of removing a key from a function I don't need?

You can kinda "erase" key bindings by trying to assign the same button to a different function, but that does not work with mod controls. Resetting controls seems to make no difference to mods as well.

"Move it", for example, gladly allowed me to bind all its functions to "page up".

[CyberVibes]

To reset key binds go to Options >Misc and click reset key mapping.

Edit: Typo

[Kerouha]

This has no effect on mods' key binds!

It will just re-bind Screenshot, Quick Load and other stuff I don't need.

[CyberVibes]

Unsubbing the mod and clearing it's config file should do that for you, be aware that the configs don't get deleted when unsubbing so will have to be done manually, the config files will be located in one of two locations, the app data Cities_skylines folder and the Steamapps Cities Skylines folder

[Kerouha]

Thanks for the help.

There actually is no convenient way of removing a single key bind.

[CyberVibes]

No there isn't and can get quite complicated if you have mods that share the keys too, it should be quite simple with a layout of a keyboard showing you whats mapped to what, a modder might be able to come up with something thats a bit simpler, the only available mod that i could find is this one, not sure if that helps in your situation tho.
https://steamcommunity.com/sharedfiles/filedetails/?id=406828238&searchtext=keybind