Api /V1/guest-carts/:cartId/items always return excluding tax

I use Magento 2.3 EE only with guest-cart api. And I want the endpoint POST: /V1/guest-carts/:cartId/items to return the price including taxes. In the following screenshot, you can see the configuration:

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I did setup:upgrade, setup:di:compile and cache:clean command but the endpoint still return the price with excluding taxes.