[noggin]

I think it’s all about giving consumers options, but setting TV defaults to something reasonable for the market you are actually pitching the TV set into. Not all home viewing environments are the same either which plays a big part. 

Exactly - which is why all of this is an admission that PQ makes little sense outside of cinemas/movie theatres. Every development seems to be about removing the hard pixel value -> absolute light level mapping that PQ dictates.  It's almost as if they are having to get TVs (and now new versions of their standard) to mitigate the false premise that the standard started with.

HLG on the other hand has no direct mapping between pixel value and light level (which also means you don't have to tone map to cope with video brighter than the display can handle, nor do you need mastering metadata), and has support for ambient viewing light level compensation (aka 'surround' (*)) built in to the standard. (I've not heard many complaints about Blue Planet II and Planet Earth II HDR - and they were both mastered in HLG, with a conversion to HDR10 for UHD Blu-ray release...)

(*) https://downloads.bbc.co.uk/rd/pubs/whp/...WHP309.pdf (You'll see the HLG standard allows for small changes in the system gamma to compensate for viewing conditions that are brighter than the mastering conditions. Mastering suites have carefully set illumination levels behind the mastering monitor to ensure consistent grading)