Color blind people could add css extension that underline / highlight links. Blind people use a screen reader / braille display, they not need an underline.

Who else needs underline?

> Color blind people could add css extension that underline / highlight links.

imo, if you're building a new library, this level of accessibility should be baked in. Given the aim of the library to have better css defaults, expecting developers to override the link styling to add underlines or expecting the users to install browser extensions to do that, feels like a weird requirement.

Underline links are subjectively ugly and it looks like outdated design.

Those are objectively bad reasons for abdicating accessibility though.

Subjectively, I also don't agree that it's ugly. There are also other options like border-bottom or dashed underline or pseudo-elements with additional symbols.

(However, I'm not sure color-only link distinction is actually an issue. It's never been considered problematic in accessibility reviews of the corporate sites/apps I work on professionally.)

the theory is everyone needs underline because not clear otherwise things are links - therefore needing underline come under people with visual disabilities but not thoroughly blind and cognitive issues like not having had any coffee yet despite being up all night, can't think of others offhand.

8% of men are colour blind. Not taking that into account when designing UI is ... interesting to put it lightly.

Afaik, there is no black/white/blue variant of color blindness.

I’m not blind or color blind, but I prefer links to be underlined as a visual cue that it’s going to take me to a different page instead of doing something javascripty.