Basically you're saying websites are the same as apps, and whether they're used in the browser or as a desktop app, the UI is fine to ditch that of the OS. Fine if you think so. I'll be sad to see OS and apps diverge completely in terms of UI.

YouTube succeeds for its content. Its UI is hot garbage both in the web and their apps. Google Maps is an atrocity and I’m very thankful Apple has decent data where I live. Roblox I don’t know, other websites I consume mostly in Reader mode.