There are a few possible reasons why errors are not being displayed in Magento 2 even though you have enabled error reporting:
The error reporting settings may be being overridden by another setting in your Magento configuration. To check this, go to the Magento Admin panel and navigate to Stores > Configuration > Advanced > Developer > Debug. Make sure the "Display Errors" setting is set to "Yes".
The PHP error_log file may be configured to log errors instead of displaying them. To check this, open the php.ini file and look for the error_log setting. Make sure it is set to a valid file path or set it to null to disable error logging.
There may be a problem with the PHP error handler. To check this, you can try adding the following line of code to your Magento index.php file:
There may be a problem with your server configuration. If you are using Apache, make sure the mod_php module is enabled and that the .htaccess file is correctly configured to allow PHP errors to be displayed. If you are using Nginx, make sure the fastcgi_param PHP_VALUE "display_errors=1" directive is present in the server block configuration.
I hope this helps!