The amount of backups in there is fairly minimal and is limited to a folder called “backups”. As for disabled features, the size of disabled features there is also relatively small, not gigabytes.

Any space reclaimed using dism’s startcomponentcleanup is only from removal of superseded updates which normally happens automatically whenever the maintenance task runs after a certain period of time.

Note that I explicitly consider backups separate from superseded updates. Superseded updates are kept for a period of time to allow the user to uninstall a newer update.