Emphasis on generally. Apple still sells many (most?) of its iMacs with spinning rust drives. Just picking up something from Apple Store and paying tons for it does not guarantee it meets minimum quality standards one might expect.
Classic hard-drives with platters that physically spin rather than a solid state SSD hard-drive. Nothing necessarily wrong with the older HDD technology, though most people have come to expect the better performance characteristics that come with newer SSD technology.
Emphasis on generally. Apple still sells many (most?) of its iMacs with spinning rust drives. Just picking up something from Apple Store and paying tons for it does not guarantee it meets minimum quality standards one might expect.