Magento 2 Email Performance Optimization: From SMTP Bottlenecks to Async Sending

Magento 2 email performance can be improved by enabling asynchronous sending, which decouples email transmission from frontend requests. This can reduce delays and connection exhaustion during peak traffic. Enable async sending in app/etc/env.php or via CLI, and verify the consumer is running. Consider switching to a transactional email service with connection reuse for further optimization.