As you've stated from the Skyrim wiki, the purpose of the tcl
command is to toggle no clipping mode, allowing you to essentially walk through walls. As you've quoted in your question, the Skyrim wiki states:
Toggle Collision. Using the TCL command with a target toggles clipping for the target. If used while falling off a cliff, may cause a crash. Useful for unsticking your character or finding items or bodies that have fallen through a wall or floor.
Functionality like this is nearly always used during the original development of the game to check how things are rendered in the game world, to observe models from a variety of angles without being restricted by the movement that the game engine allows by default. It could also be used in this manner during the development of modifications for the game, and finally, it could be used by the player to run around the game world for fun when bored. There are other uses, but these are already detailed in the excerpt from the Skyrim wiki above.
Wikipedia has the following to say about the uses of no clipping;
Noclipping can be used to cheat, avoid bugs (and help developers debug), find easter eggs, and view areas beyond a map's physical boundary.