It's the same slider, the classic label is only in the builder. And the slider element doesn't have those options (padding, margin, and more) as the slider will just ignore those depending on your slider settings. I recommend editing your slider directly and change the spacing options as it's not possible within the builder.
Plus, classic elements have fewer options. So please use the new elements as much as possible . But since slider doesn't have a new element counterpart, your only option is to use the classic slider.