I don't really have have any complaints, it's really easy to tell which tab is where and the mouseover makes it even clearer. Does it look better? Maybe. Does it function worse? No.
If I slow down and pay attention I'm OK, but it's definitely less functional for me.
Fixed it for you.
What are we to do? Obviously we have to design for the majority. I presume there are high-contrast modes that can be enabled if you need that.
That isn't obvious to me. Why remove things that were helping the minority and not hindering the majority?
You're gonna have to actually defend the notion that having borders around interactive UI elements is "clutter". Calling it "clutter" doesn't make it "clutter".
> I presume there are high-contrast modes that can be enabled if you need that.
I don't, but I also don't see a reason to make "inaccessible" (or even "less accessible") the default.
Ultimately we’re all just giving opinions and a proper study should be done if people want to argue either way. Until then it’s up to the devs as the people doing the actual work I guess.