I came across a list of monospace-styled sites. These are some of my favourites.

• https://musicforprogramming.net/latest
• https://commitmono.com
• https://owickstrom.github.io/the-monospace-web
• https://wttr.in
• https://plaintextsports.com
• https://chimbosonic.com

I like the idea of using monospace everywhere on a site but I think it only works when you go all in on the theme. ASCII art, terminal style, etc.