This is very disingenuous. The colour gamut is low because they are using it in PC mode(which means sRGB is going to be displayed) and not HDR mode, so the TV won't show its full colour gamut. The gamut is lower because the white point is incorrect from what I see, with a lot of green bias leading to less red.
No decent panel manufactured in the past 3-4 years would have this bad of colour gamut on full gamut mode, i.e. in HDR displaying BT.2020 colours.
Now coming to brightness, they themselves said they are not measuring HDR brightness, and this is full field brightness and not 10%. 600 nits on SDR over 100% of the screen is extremely bright just so you know. This means that the TV will certainly hit 850-900 nits on a 10% window in HDR.
Here you can see it covers almost 97% DCI-P3, which clearly proves my point to how wrong the testing in the above case was. Testing on PC mode for a TV clearly not meant for it is a recipe for disaster. This will be a horrible TV for connecting to a PC anyway.