This is Safari. Apple made this, presumably saw this, and said "yeah, send it"
Yup. So far the only thing I've seen that stops this is 'Reduce Transparency', but many people don't like the side effects this setting creates. In other words, one of the main beefs people have with Liquid Glass, that being the one you point out of gradient-infused scrolling content at the top and/or bottom of the screen underlapping existing content there, isn't even addressed by its new 'Tinted' setting.
Oddly, today I found that while
Display & Brightness > Appearance > Liquid Glass won't let you select 'Tinted' unless you have 'Reduce Transparency' and 'Increase Contrast' turned off in
Accessibility > Display & Text Size, you can turn them off, then select 'Tinted' in the
Liquid Glass prefpane, then go back into
Accessibility > Display & Text Size and turn on 'Reduce Transparency' and 'Increase Contrast' again, then go back into the
Liquid Glass prefpane, and you'll see 'Tinted' is still selected. Not sure if that adds something on top of these settings, or if it just switches 'Tinted' to 'Clear' without showing that change in the Liquid Glass prefpane.
At least Apple is consistent with their inconsistency.