Issue with WordPress Plugin Activation Hook and Table Creation

Not sure if this helps but try doing this in the main plugin file:

require plugin_dir_path(__FILE__).'inc/plugin-setting.php';
require plugin_dir_path(__FILE__).'inc/db.php';

// Register activation hook in the main plugin file
register_activation_hook(__FILE__, 'wp_comment_reactions');

Move your function wp_comment_reactions to the db.php file and call it from the main plugin file.