The moat is real! I haven't tried recreating Liquid Glass in the browser yet. From what I've seen, it's possible, but not in a practical, cross-browser, "can be applied to an arbitrary component" kind of way.

Of course, as soon as we figure out how to get it done, Apple will move on to the next thing. I'm okay with that though. It was a bold move, and I can't imagine how much time and money Apple spent making Liquid Glass look that good.