Starting from version 1.17.0 of the Shipping Table Rates module, it is possible to use Shipping Areas when configuring shipping rates. To enable the functionality, you need to install the 'amasty/module-shipping-table-rates-to-area' package from the composer suggest section (the features are available within an active subscription).
When the module is installed, the Apply Rate by Shipping Area option is available in the rate configuration.

When the Apply Rate by Shipping Area setting is enabled, the following destination fields are hidden from the rate configuration:
Country
State
City
Zip