I've been seeing this myself since I use several Apple products, and while parts are done well…
> though the desktop experience suffers slightly (of course).
This is the part that makes it not work. The Liquid Glass transition isn't the only thing that's negatively impacted desktop UI in macOS, but also the several revisions of iOS-7-like flat designs since 10.10 Yosemite with a slow but constant march of papercuts. So even in the prior version (Sequoia), a great deal of damage had already been done. Tahoe's Liquid Glass compares less favorably against the much more "desktoppy" 10.9 Mavericks.
Trust me, I'm with you 100%. I weep for the Mac OS X we used to have.
I'm just trying to look at it from Apple's eyes. From their perspective, I think, they're trying to design a UI framework that exists beyond any particular device form factor. UI design in the abstract, where specific platforms are particular manifestations of their Platonic UI ideal.
So you have something of a broad convergence of macOS / iOS / iPadOS / visionOS / etc. design elements, like rounded application windows, UI widgets (button/toolbar/...), ecosystem stuff (app widgets, live activities), and Apple technologies (Control Center, Spotlight, Siri, notifications).
Layout is (mostly) grouped relative to display size, not interaction method (like touch v. mouse). Similar display sizes have similar application layouts. Large = (macOS, visionOS, tvOS, iPadOS), medium = (iOS, iPadOS [small devices], CarPlay), small = (Apple Watch). Large display layouts tend to have the menu bar, toolbars, and side bars.
I could go on but it's getting late. This might be a half-baked idea, but I'm pretty sure this is more-or-less how Apple is approaching their platforms now with the Liquid Glass redesign.
> though the desktop experience suffers slightly (of course).
This is the part that makes it not work. The Liquid Glass transition isn't the only thing that's negatively impacted desktop UI in macOS, but also the several revisions of iOS-7-like flat designs since 10.10 Yosemite with a slow but constant march of papercuts. So even in the prior version (Sequoia), a great deal of damage had already been done. Tahoe's Liquid Glass compares less favorably against the much more "desktoppy" 10.9 Mavericks.