It’s used very often on ycombinator in submission titles and comments. I see it used by millennials and gen z on Discord, though more commonly as an adjective, eg ‘oh is it just web or is there an app?’
Sometimes they drop ‘the’ and it becomes “hey i saw this on web.” Online Korean comics are usually just called webtoons instead of manhwa. It’s used on corporate sites, ads, hotel amenities descriptions and in references to ‘the dark web.’
What more do you need?
We really don't, because technical accuracy isn't relevant to the vast majority of people, who aren't discussing protocols to begin with.
And anyway,I think people stopped referring to "the internet" in general once it became ubiquitous enough that it became more useful to refer to specific sites instead, or genres of services like social media. I think the only time people use "the internet" anymore is in reference to their ISP, eg: "the internet" going down.
For example, I assume all the "apps" don't count as WWW? But some services (most?) have their web versions, so it's kinda hard to distinguish.
However, all of these run on top of the Internet Protocol (IP). So, everything is internet, but not everything on the internet is http.
Apps are almost certainly using HTTP under the hood to communicate with their servers, so technically they are a part of the web, which is a part of the internet.
It had that girl from the bus.