the liquid glass ends up being vital for windows in AR. the vision pro has this, and it really helps you see behind the windows you've placed. while a shit experience on a phone, i do think liquid glass is a useful choice in the AR world
Back in my day (as far back as a month ago), we just called that effect “transparency” or “translucency”.
Hell, there are types of AppKit popup windows that have the effect on by default, that have existed untouched since the early days of Mac OS X.
Don’t give Apple more credit than they deserve here.