The configuration file that's suggested to force a font to show up as monospace is very helpful, but it appears you may need to force fontconfig to rebuild the cache in order for the change to take effect.
= kitty - the fast, featureful, GPU based, terminal emulator See https://sw.kovidgoyal.net/kitty/ image:https://circleci.com/gh/kovidgoyal/kitty.svg?style=svg["Build status", link="https://circleci.com/gh/kovidgoyal/kitty"]
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