That's normally simply due to the learning/experience curve of the TV industry.
Happened with plasmas, happened with HD Ready TVs, 1080p, 3D, curved, 4K, and HDR.
4K HDR sets will in the next few years be at the circa 'Ł300 for 50 inch' range...and then 8K or 16K or Ultra Super Mega HDR will come out