I don't think this is fair to XV. Obviously, if VII were reworked to be executed well by modern standards, it'd better than a game that fell short execution-wise. That's just implied by the terms of the hypothetical. But if you're going to give VII the benefit of that hypothetical, it's not particularly meaningful to compare that hypothetical to a real game that was subject to real production pressures because it actually exists. XV doesn't exactly lack a foundation on which better execution couldn't have improved. (It certainly has a more solid ending!)
It's also worth pointing out that executing VII to a modern standard would require a lot more changes than people tend to assume. Like... FFVII has a woman problem. Aerith is fridged and kind of lucks into helping to save the world because of it. Tifa abandons a party leader role to go take care of Cloud even though the world's ending, and her outfits and the camera angles used to show them are... questionable at best. Oh, and you can go into her drawers and look at her panties, because, why not? Don Corneo is a sexual threat to both Tifa and Yuffie (who, by the way, is a teenager). The situation with Lucrecia is pretty messed up. I think Elena had a thing for Tseng. And the less said about Scarlet, the better (that slap fight, *sigh*). The remake will probably get some leeway because it's a remake, but if a new game handled its women that way in today's environment? I think there'd be a big problem.