The Verge is selected in the *second* one and is the lighter color, but in the first one, Google News is selected and it is the *darker* color...which is my whole point.
I don't know how people are seeing this. I'm on Safari 15.0 with the new tab design, and for me the active tabs is highlighted in a bright colour. The other tabs are shaded dark.
Also, If you have lots of tabs then the active tab is also much larger than the others. It's 100% clear what the active tab is.