Lack of Dolby Vision and HDR10+ on 4K UHD

[Adam4Rizzel]

Is there any reason that major studios still decline to offer Dolby Vision and/or HDR10+ on their 4K discs? I've heard about the additional DV layer, but it seems odd considering that they offer Dolby Vision on the streaming version of the same titles. This seems to be a trend from Sony, Universal, WB, and Disney/Fox for both recent and catalog titles.

It's a strange conundrum because it makes you chose between an option of better color and dynamic range, lossy audio, and high video compression and an option of lossless audio, high bitrates, but lower quality color and dynamic range.