I watched someone play FF7 OG for the first time over the weekend, and something struck me as interesting. When it got to the point where they were digging into Cloud's past and the big reveal of Zack being the person who was actually in Nibelhiem, the streamer had no fucking clue who it was or why any of it mattered beyond Cloud really just being the grunt dude and having made it all up. The streamer didn't find the extra scenes in the game where it shows Zack save Cloud from the experiments in the Shinra mansion and take him to Midgar, nor the scene where the soldiers unload guns into Zack's body.
This struck me as an interesting aspect of the Remake Trilogy as well as why they remastered Crisis Core. Zack is very important to Cloud's story and in the original game he's very badly used. My guess is part of the whole reality twisting and putting Crisis Core out there, is entirely to give new players the opportunity to relate to Zack and know who he was, so that the truth of what Cloud's been through makes more sense and everything ties together better.
That's my theory on it. Because as great as FF7 is, a lot of the writing was not great.
FF7 became a beloved classic and Cloud a popular character because his story resonated with people back then, not because they knew that in the future crisis core would be made and Zack would become important.
Not knowing who Zack is not a problem, he's pretty much irrelevant to the core story. The point is that Cloud wasn't a soldier, he failed to become what he said he would and was so ashamed of it he didn't even dare meet up with Tifa. But, despite being a lowly grunt, when Sephiroth killed his village/mom he still had the courage to go up against his former idol and wound him. Most story hero are about chosen one who are predestined to success, all they have to do is not fuck up (something which they can typically barely achieve), Cloud initially seem like that, the big shot solider. But it turn out, he's not, he's just a nobody who still managed to achieve greatness. This is reinforced subtlety throughout the game, character that should recognize Cloud as a soldier don't, Sephiroth can't even be bothered to interact with him for most of the story (and then just use and discard him).
The new canon reverse that, now Cloud is a big chosen one and everyone is obsessed with him. As far as Zack role in this story, it's little more than just to answer the question of how Cloud went back to Midgard and why he became a mercenary. Someone playing trough the game and not realizing who he is isn't an issue, he's just an easter egg for people who want to dig deeper.
Speaking as somebody who's only played the first Remake, and not Rebirth yet: if it was too much the same as the original, I'd be willing to put money down that in the universe where it was closer to the original text, a lot of the same folks complaining about how it's unfaithful here would complain about it being pointless there. Not to throw any shade on you as an individual, or to imply that you actually don't want something more like the original, of course. I'm just saying that a remake also needs to change things, and not just recreate the original shot for shot with better technology and different actors. Times change and so do audiences; expecting media to stay the exact same forever, other than the FF7 PS1 disc you presumably still own, isn't something I can get behind.
I mean, I'd like to play a game where the character in the game have, you know, hands, just that would make the remake worth it. Look, in a perfect world, square would still be banging out amazing game year after year, with a great mainline FF game every 3-4 years carried by moving story. In that world, I: 1) wouldn't really care about remaking FF7 and 2) wouldn't mind if they changed the FF7 story (because they presumably would still have good writer on hand).
But this isn't the world we live in, Square output as been pretty disastrous in the last decades or two, with most game having horrendous story and them taking almost a decade between new FF entry (which are all pretty disappointing with pointlessly convoluted bad story, to say nothing of stuff like kingdom heart "story"). In this case, them faithfully remaking game is a lot more appealing because they clearly can't write anymore, but maybe they can copy their own homework successfully.
In other word, this what I think current Square is doing.