I was an nvidia fan at first too, but when I upgraded from geforce 4 to Radeon 9700 the difference in picture quality was like night and day, and I realized how stupid I was for believing all the fan boy stuff. Since then I have preferred AMD and have been very happy with all of their products that I have owned. I have owned nvidia cards since as well (was there a 6600, and 8800 gts or something). Usually I buy best bang for buck, and over the years I feel lucky enough to have owned the best card per generation.
I still suspect there is some cheating going on. But in my opinion for the relative cost it seems that nvidias cards always get around a 10 fps advantage, but the picture quality always looks worse. Always. But now days theres just so much weirdness about tech, Denial or bias or whatever. You just can't take anyones word for anything. I can say the quality looks better but you can just write me off as a fanboy and vice versa. We really don't know the difference, and neither of us are really qualified to weigh exactly what is happening. I will say I am probably more qualified than most of the popular youtubers that educate people though.
Now AMD is not immune to this "cheating". I can see that something has changed across all of their chips (GPUs, PS4) since about driver version 15 or so the cards aren't rendering surface textures the same. Its super evident in Uncharted 4. Some of the textures used to have a rough look about them... Like they would be rough if you touched them. Those textures are not rendered the säme now. That rough look is replaced with a blurry look. Same goes for PC in games such as The Witcher 3, and Rise of the Tomb Raider.
Is anyone keeping an eye on this stuff? What I think we really need are actual qualified people to talk about it rather than well the usual youtuber who's life experience consists of playing video games... Has anyone else noticed this difference I am seeing? I think its texture filtering but I am not sure. This kind of shit should be taken into account.
Also, I am pretty disgusted with gpu partnerships and how just about every single port with nvidias seal run better on shitty console hardware. The bias fanboy shit becomes an issue here too. Evidently that comes down to opinion somehow.