Hi and Welcome to the Forum Varleyst.
The Last used on Column which by default appeared in Windows XP, was effectively deprecated by Microsoft in Windows 7. Even in the prior Vista, the column was hidden, but could be reinstated just as you discovered you can do in Windows 10.
The reality is it was never a reliable or accurate feature because while an application may have a registry entry point, that point did not contain information on the executable so there was a best guess used to give you a last used date.
If you right-click on the executable for an application, then select Properties > General tab you will notice at the bottom is a Last Accessed date. Even this is not particularly reliable, but it atleast still exists in the Windows 10 OS by default.
As to why Microsoft continue to allow a User to check the option to display this deprecated Last used on column, well that is anyone's guess.
Regards,
Regedit32