The real reason for lack of interest is streaming quality of 4k has been getting worse for years, and is still like 1/10th the quality of 4k BluRay, with enormous levels of compression and artifacts.
8k requires 4x the data. We all know that means every subscription would charge at least 2x more to maintain profit margins of unlimited growth for vulture capitalism, and they’d skimp on the extra data too; leaving users with nothing better than the current 4k.
Yeah, storage/bandwidth is the overall limiting factor regardless for 8k. Also, most peoples xp with 4k is streaming, so there would likely be 100x more of a market for increasing bitrate from the current “compressed as all fuck” up to 4k Bluray bitrate, before anyone cares about 8k… but of course, that isn’t something that TV manufacturers can control or use to sell more products.