Each Game In The Final Fantasy VII Remake Will Have The Same Amount Of Content As A Mainline Game
During a behind-closed-doors appointment with Square Enix for the Final Fantasy VII remake, producer and original Final Fantasy VII director Yoshinori Kitase gave a presentation about various aspects of the new game. As if to head off the inevitable questions about the remake's content split at the pass, Kitase remarked that the first game focuses just on the dystopian metropolis of Midgar and that, while limited to that city, it has as much content as any mainline Final Fantasy title.
While they weren't willing to dive too deep into the split, Kitase explained that they are doing it this way so that they can reimagine the game in a modern context without losing anything that was in the original title in terms of environments. This means a massive expansion of the ideas from the original title. As shown in the Square Enix E3 presentation, bosses like the Guard Scorpion from the first Mako Reactor have been developed to be longer fights.
There is definitely a lot more content that would make the original game's opening act feel longer, though in what other ways like side quests or cutscenes, remains to be detailed. Final Fantasy VII Remake is releasing on PlayStation 4 on March 3, 2020.