Firstly your entire point rests on the assumption that FF VII is the better game. Just because it came out better on better technology doesn't make it the better game.

Secondly, there are so many problems with the parent metaphor that I don't even want to get into that one. XD

Finally, it's not about graphics, at least not entirely. It's about Aesthetic appeal, (I will always hold that art design trumps high end graphics myself, but that's beside the point.) FF VII's character models have aged badly and look pretty clunky. FF VI's have aged much better. However FF VII is clearly the graphical power house by comparison. (Mind you, I do just mean the character models, a lot of the backrounds and locations do look great, as well as the FMV's have aged well.)

Given the visual nature of a video game, the aesthetics are very much a valid point to bring up. You are, after all, constantly looking at the visuals your entire play through, this is going to have an effect on your opinion.