Yeah, I seriously think that if there was any other, more advanced home video format, it would increase the bitrate rather than resolution. Many movie theatres have 1080p digital projectors and the PQ is stunning and the studios could use their uncompressed master files made for blu-ray (not necessarily a good thing but the studios would probably support such format for convenience). Even if there were TV screens and home projectors with a 4K resolution, I doubt that at screen sizes that could fit into a reasonably sized living room there would be any perceivable difference between having a true 4K master or an uncompressed 1080p one.