"Arguably, 8K might not really make sense at sizes lower than 55 inches, [...]" Why not? Many smartphones have a pixel density of 400 ppi. A 32 inch 4K monitor is only 163 ppi. Some people claim that at a certain eye-to-display distance pixel densities higher than x cannot be perceived. But anyone actually having seen first-hand the fidelity of text on an FHD monitor, a 4K monitor, and a 5K monitor knows that this is not true.
Price will indeed be the operative factor. As of writing, 8K-width monitors that aren't ultrawides (ultrashorts) are still sparse and expensive.
Yes, not much reason to hope this one will be inexpensive. Luckily I don't have to wait for this monitor in particular, the reflections off its glossy screen are a deal-breaker. But perhaps AOU, Samsung, and others will bother to compete. And in a few years 8K might be a viable option.