W3schools, which some find authoritative for HTML and DOM, says:
By default, links will appear as follows in all browsers:
- An unvisited link is underlined and blue
- A visited link is underlined and purple
- An active link is underlined and red
You can see this in action at another authoritative site:
html.spec.whatwg.org
For example if you have a stylus you can hold it on a link and see the color change to red during the click, then lift the stylus and the color changes to purple.
The defaults are just that, they can be modified if desired.
So it appears that underlining still has sway. The link I created above is manually colored and underlined. Normally the underscore sould be the color of the link. Crikey it's been sometime since I dealt with this stuff.