Hardly visible. A torture for the eye. If you insist on colors, please use plain red.
You should open a ticket with Certbot on GitHub - certbot/certbot: Certbot is EFF's tool to obtain certs from Let's Encrypt and (optionally) auto-enable HTTPS on your server. It can also act as a client for any other CA that uses the ACME protocol.
Certbot doesn't choose these colors. I believe those are just the standard exception logging colors from either pywin32 or the windows interpreter, and I think you can override them with a custom color scheme.
This venue is for feature requests, is it not?
For LetsEncrypt, the ACME CA that Certbot uses, yes.
Several years ago, EFF.org took over the development of the Certbot ACME Client. Old documents still point users here. Their staff and developers do not regularly check this forum.