Are the events surrounding the final fantasy characters canon to the franchise sort of like how dragon ball gt is canon to its own timeline but not to the main canon?

I was just thinking about this and I want to ask a question if I can answer this myself since I’m not a fan of Final Fantasy (only bc I haven’t played any games besides that the games look fun I’m not trying to hate) at what time frame does Clouds world get devoured by darkness bc Aerith is still alive I know she’s alive in the game bc they needed her because she was popular at the time but there also has to be a lore explanation to that you can’t just say “she’s alive in kh because she more was popular than Tifa at the time”