Windows keeps every driver you have ever installed, including the old ones

C:\Windows\System32\DriverStore\FileRepository holds a copy of every driver package Windows has installed, including every superseded version. On a machine with graphics drivers updated monthly for three years, it is one of the larger folders in C:\Windows.

Why it keeps the old ones

So that Roll Back Driver works. When a new graphics driver breaks something, Device Manager can put the previous one back, and it can only do that because the package is still there. That is genuinely useful and it is why this folder should be pruned rather than emptied.

Seeing what is in it

pnputil /enum-drivers

Run it in an administrator prompt. Each entry has a published name like oem12.inf, the original name, the provider and the version. Several entries from the same provider with different versions is exactly what you are looking for: the highest version is in use and the rest are history.

Removing superseded packages

pnputil /delete-driver oem12.inf /uninstall

That removes one package. Windows refuses if the driver is currently in use, which is the safety net: the command cannot remove the driver your hardware is running on. Add /force only if you know exactly why you are doing it, because that removes the refusal along with the protection.

The easier route for the common case

Disk Cleanup, in its system files mode, has a Device driver packages category that removes superseded packages without naming them individually. It is more conservative than doing it by hand and it is enough for most machines.

Graphics drivers specifically

Nvidia and AMD installers keep their own copies outside the driver store, in C:\ProgramData or their own folders under Program Files, and a clean installation option in their installers removes the old ones. That is separate from the Windows driver store and worth checking on the same pass.