You're putting words in my mouth again. Where did I say that nVidia cards were better than AMD? I said that Apple excluded nVidia cards from Macs, and that they didn't do it because AMD cards were better.
Also, that "one of them has to be excluded" is wrong. The Mac lineup has almost always offered a mixture of AMD and nVidia cards, and Apple used to switch vendors at every update. They even frequently offered options for GPUs from the two vendors in the same line of Macs. Once, Apple excluded ATI for a year or so, which everyone noticed and saw as a punishment for ATi's CEO dropping the ball on the new sunflower iMac ahead of the keynote (this is documented). Steve apparently didn't appreciate. Now they're doing something similar to nVidia, for god knows why. Some speculate that it is to disfavour CUDA. I've read that it's a response to nVidia's threat to sue Apple over some patents related to AX chips. What pisses most users here (not just me) is that nVidia cards have been way better in terms of perf/watt, and would have been a better fit in the 2014-2015 laptops and iMacs. Yes, I'm saying nVidia cards have been better lately, but I haven't until now (note also that the all the standalone cards I've purchased were from AMD/ATi).
You've put words in my mouth twice, and you're trying to defend Apple with weak arguments ("one has to be excluded"). Now you're almost characterising me as a fanboy. If you think that criticising Apple for excluding nVidia cards, for not supporting Vulkan, or for neglecting OpenGL + OpenCL is criticising Apple for the sake of it, then I don't know what to say. Read my posting history and see that I have defended Apple's decisions (and Metal) many times here, when I think they are justified.