When creating an acf block, I cannot see the category (useful for block filters)

Registering the example block in the documentation:

add_action('acf/init', function() {
    if( function_exists('acf_register_block_type') ) {
        // Register a testimonial block.
        acf_register_block_type(array(
            'name'              => 'testimonial',
            'title'             => __('Testimonial'),
            'description'       => __('A custom testimonial block.'),
            'render_template'   => 'template-parts/blocks/testimonial/testimonial.php',
            'category'          => 'formatting',
        ));
    }
});

And then filtering the allowed post types, the category appears as NULL instead of formatting:

add_filter( 'allowed_block_types_all', function ($allowed_blocks) {
    // Get widget blocks and registered by plugins blocks
    $registered_blocks = \WP_Block_Type_Registry::get_instance()->get_all_registered();
    // ⬇ Uncomment to see the category of each block
    echo '<pre>';
    var_dump($registered_blocks);
    echo '</pre>';
    wp_die();
});

["acf/testimonial"]=>
  object(WP_Block_Type)#17360 (21) {
    ["api_version"]=>
    int(1)
    ["name"]=>
    string(15) "acf/testimonial"
    ["title"]=>
    string(0) ""
    ["category"]=>
    NULL
    ["parent"]=>
    NULL
    ["icon"]=>
    NULL
    ["description"]=>
    string(0) ""
    ["keywords"]=>
    array(0) {
    }
    ["textdomain"]=>
    NULL
    ["styles"]=>
    array(0) {
    }
    ["variations"]=>
    array(0) {
    }
    ["supports"]=>
    NULL
    ["example"]=>
    NULL
    ["render_callback"]=>
    string(25) "acf_render_block_callback"
    ["attributes"]=>
    array(6) {
      ["id"]=>
      array(2) {
        ["type"]=>
        string(6) "string"
        ["default"]=>
        string(0) ""
      }
      ["name"]=>
      array(2) {
        ["type"]=>
        string(6) "string"
        ["default"]=>
        string(0) ""
      }
      ["data"]=>
      array(2) {
        ["type"]=>
        string(6) "object"
        ["default"]=>
        array(0) {
        }
      }
      ["align"]=>
      array(2) {
        ["type"]=>
        string(6) "string"
        ["default"]=>
        string(0) ""
      }
      ["mode"]=>
      array(2) {
        ["type"]=>
        string(6) "string"
        ["default"]=>
        string(0) ""
      }
      ["className"]=>
      array(1) {
        ["type"]=>
        string(6) "string"
      }
    }
    ["uses_context"]=>
    array(0) {
    }
    ["provides_context"]=>
    NULL
    ["editor_script"]=>
    NULL
    ["script"]=>
    NULL
    ["editor_style"]=>
    NULL
    ["style"]=>
    NULL
  }

Reproduce the issue with the documented PHP registration and inspect the values returned by WP_Block_Type_Registry through allowed_block_types_all. Trace how acf_register_block_type passes block metadata into the registered WP_Block_Type; done means the category is available as formatting rather than NULL. The payload names no source file or test, so locate the registration implementation and related tests first.