Unless you have someone trying to sell you a GZ2000 or are discussing one with a new owner, trying to justify their purchase, I'd expect this to be the view of anyone comparing it with a top tier 2018 or 2019 display. The fact is that OLED has reached it's pinnacle already and any improvements this year, will be barely evolutionary, let alone revolutionary.
What I'm expecting from the pro reviews is that the GZ2000 is very accurate out of the box, when compared to the various SMPTE/ ITU standards, possibly negating the need for a calibration. It has a peak white luminance measurement of around 900 nits, in the appropriate HDR mode.
It seems no pro reviews pick up on uniformity issues, so that will be left to reports from owners, on this forum. Seems great so far though.
Tint is another one that always seems to be perfect on review samples, so this again, will be left for the end users to report.
Most of the OLED displays nailed near black performance in 2018, so any improvement here will probably be restricted to displaying that part of the picture without artefacts.
That's probably about it, from a purely PQ perspective. I should also point out that I'm not trying to detract from those who've bought a GZ2000,it's still at the top of my list.
Paul
ETA: Almost forgot, those pro reviews that bother to actually evaluate it, will see an improvement in IR on the GZ2000 over all the other upto and including 2019 OLED's, due it's bespoke power handling electronics.