We set --bs-border-opacity: 1 globally at the :root level, so redeclaring it on every .border-* utility doesn't make much sense. I think we can drop this.
Edit: Per conversation below, I've also removed the global --bs-border-opacity and restored it on the .border-{color} utilities. There's no need for border opacity on default .border utilities, just the color ones, which now properly matches our .text-{color} and .bg-{color} utilities. In addition, this rearranged the utilities map to put border-color at the end (without which .border-opacity-* classes wouldn't work properly.