Your example is exactly why we have both History.pushState and History.replaceState[0]. The core question there is whether a new slide represents a new page or not. And in this case, I agree that it doesn't: it's the same page, just in a different state.
EDIT: If you mean one of those 20-image slideshows intentionally made to create fake click statistics, I agree that that's absolutely infuriating. But in that case ergothus' comment applies: the real problem is bad faith webdesign in that case.
And this example pretty much nails the theme: there is no technical reason for these problems. If a website screws it up, it's just bad design at this point.
EDIT: If you mean one of those 20-image slideshows intentionally made to create fake click statistics, I agree that that's absolutely infuriating. But in that case ergothus' comment applies: the real problem is bad faith webdesign in that case.
[0] https://developer.mozilla.org/en-US/docs/Web/API/History#Met...