I think that's exactly why I'm having a negative reaction to the redesign as well. I'm expecting page tabs, not pills. I'm also finding the excessive roundness terrible.

Of course, I'm on Windows, where it doesn't make any sense to incorporate Apple's Liquid Glass design guidelines. When I do want an Apple-like interface, I'd rather have something from the 10.11 - 10.15 vintage please. I wouldn't mind if there was a clearer option to switch back, but I'm not seeing that in the Appearances preferences.