not just fiber, e.g. Netflix requires "only" (reliable) ~15Mb/s for a 4k stream, that means most people in most countries feel little difference between ~25 Mb/s and 1Gb/s in their "every day" usage. Sure it's a huge difference if you download a 80GiB AAA game, or preload a 4k movie. But in my experience (which definitely doesn't apply to all countries) a lot of non tech affine people don't do that that often an if they do it (e.g. movies before travel) they tend to do it over the night so it still works out just fine with not so fast internet.

So for a lot of people paying for more then 25-50Mb/s (pro person) makes only sense if it isn't too costly. Hence I rarely see people going for more then 250-500 Mb/s even iff 1Gb/s is available and they have money. And for non-gamers with little money, I mostly see them with ~50Mb/s (or paying for 50Mb/s but getting much less due to old wires :( ).

(Also IMHO The more important things compared to 1Gb/s is how much of the bought bandwidth is reliably available at all times _with good latency_...)