You're only attacking his character instead of showing/proving he's wrong here. I don't see how that's more convincing than a video showing the effects of G-Sync on the C1.
If he's being bad faith here(knowingly using a FW where it hasn't been addressed or using bad settings) it should be easy to show that G-Sync doesn't come with a big brightness hit he's shwoing.
You can even clearly see the (User) in the brackets, meaning he edited the Preset so there is no way of knowing what he actually changed since he doesn't show the actual settings, which should always raise some eyebrows.
I'd only trust stock preset comparison when comparing modes without showing the settings and, that is yet without proof though, I have reasonable doubts about his claims. Since the Panel is capable of 120Hz and OLED is self-lit, I see there no reason why Brightness is supposed to be lower with a variable latency on. AFAIK Vincent even showed that OLED Pixels don't even need 1ms to display a new color so, technically speaking, there should be no loss in brightness as the pixel easily can change colors and adjust brightness way way faster than even the time it takes the TV to change all the pixel on the TV.
My HDMI 2.1 Cable actually just arrived and I plan on definitely checking this out this evening or tmrw since so far I only had a 2.0 cable since my old screen was 4k 60Hz only.
If you want, I can tag you in a follow up post to this or reply to this comment again when I post my findings about how the settings compare at default settings and how my subjective perception is of possible brightness differences and if there is a difference the options for someone to adjust them.