Magento 2: How to change the default country in the "Estimate shipping" block in cart?

General -> Country Options -> Allow Countries was bugged until 2.1.

Instead to have a default country (Spain) in cart shipping quotes you have to set it in

Tax -> Default Tax Destination Calculation -> Default Country.

I continue to don't understand what General -> Country Options -> Default Country means if it is near to Allow Countries that is referrred to shipping quotes.

It is struggled.