These images from the Creator Studio announcement perfectly illustrate the failure of Liquid Glass.
It doesn't get out of the way of your content — it INVADES your content.
This is an image editor! Yet HUGE regions of the image are invaded, blurred, and obscured by translucent UI, making both the image and the UI worse.
Low-contrast UI on blurry content doesn't clarify anything or get out of your way — it distorts the content AND the UI into an ugly, unusable slurry.