Bricks terms query variables can be manipulated before the query runs like so:
add_filter( 'bricks/terms/query_vars', function( $query_vars, $settings, $element_id ) {
$query_vars['exclude'] = 23; // Exclude term id 23
return $query_vars;
}, 10, 3 );
The filter callback receives three arguments:
$query_vars
an associative array used to feed the WP_Term_Query class$settings
an associative array containing the element settings set in the builder$element_id
is a string containing the unique element ID