WooCommerce creates transients with names like product-transient-revision and uses their values (timestamps) to cons up the names of other transients. Deactivating a persistent object cache plugin makes those transients' values revert to whatever they were before the object cache was activated. That is, they revert to stale values. In turn that means that other stale transients get used to look up variants and other product stuff.

This way of using transients made it into WooCommerce as a fix to their performance defect #5777 .

The fix to this plugin is to delete all transients from the database upon activation and deactivation, so no stale values are left.