The whole appeal of the Midgar section for many fans though, is the fact that once you finally manage to escape the city...you quickly realize it was basically an extended tutorial section that has prepared for you venturing out into this infinitely larger and more complex world. Fans of the game often talk about that incredible feeling they got when they stepped out onto the world map for the first time, where it slowly dawned on them that the story was literally only
just beginning. It does so much to establish the vastness of the world, as well as to evoke a kind of yearning for exploration that becomes vital to the player throughout the rest of the adventure.
In my opinion, if you literally transformed the Midgar prologue into a fully fledged, entirely separate installment as opposed to the rest of the game, it would not only disrupt the flow of the game at quite a fundamental level, it would almost kind of miss the point of why the Midgar section was chosen to serve as the prologue for the original game in the first place. It would ruin what made Midgar work so well, from both a narrative and gameplay perspective.