My comment was a bit flip, sorry.
One other issue is the number of users who have a collection of 3D material. afaik there are no TVs that do both 3D and HDR so those 3D displays are going to be around for a while. Those users may want to future-proof their library by buying new films in 4k.
There are plenty of 2016 and one or two 2017 models that do both. In particular the LG C6, E6 and G6 do HDR10 and Dolby Vision, and are also the best 3D TVs ever created.
I don’t see this leading anywhere. It’s quite nice to be able to play anything with any TV. Even HDR on an SDR display. Why not? 
I’m doing this with my VT50 plasma TV which I would only trade for an OLED, but rather wait some more time for MicroLED. Therefore I have 4K releases on disc already with 3D audio that I have a sound setup for. Those I play via my Panasonic 424 UHD player (or 420 in the US) and 4K files I can play via my Vero. It would be superb to get some HDR to SDR conversion similar to what the Panasonic can do. 4K HDR discs played with it using the tone mapping as well as the BT2020->BT709 dithering and the HDR Optimizer while outputting 10bit deep colour look just like they were meant to look like that on my SDR TV.
My projector can do HDR/HDR10+ and 3D MVC.
Granted, it’s not a TV though.