If you hold a website and use SSL/HTTPS with Certificates theres is often the question should i block Port 80?
The most Admins think after the Major Changes of the Browsers to pull first HTTPS Port 443 they can close the HTTP Port 80.
But you should NOT do it! Why? most Bots scan at first Port 80 for Content or for Listening Web Servers.
More Details: https://letsencrypt.org/de/docs/allow-port-80/